Curious about a pitcher and bowl I bought at an estate sale - it has
markings on the bottom.  How can I find out what brand of dinnerware
it is? Is there a site with all the markings available so I can look
for it?

Hi tacoma, 

The short answer to your question is No. 

Unfortunately, there are no comprehensive illustrated directories
online that would allow you to browse all of the world’s backstamps
(or even just your country’s). The reason for this is sheer quantity. 
Take a look at this list of encyclopedias of backstamps and potter’s
marks and note how many there are in each given domain –

http://ceramicbooks.com/ancient.htm

However, all is not lost. It still should be possible for you to
identify the maker of your dinnerware.   The identifying marks you are
referring to are known as Backstamps or Maker’s Marks and yes, there
are ways to identify the brand of dinnerware you have purchased.

First try the site below. It is certainly not comprehensive, but does
provide a clear look at the largest collection of backstamps I was
able to find online ---

http://www.ohioriverpottery.com/

In the search box type: BACKSTAMP

Then click on any of the results for some very clear pictures of
backstamps on various dinnerware.

If you found nothing there that matches your marks, then read the
following sites to get further information on how to identify your
dinnerware ---


---------- BASIC INFORMATION ON IDENTIFYING DINNERWARE ----

“When trying to identify your dinnerware, there should be three names:
the maker's, the shape and the treatment. This last name is usually
the most difficult since treatments were mainly named by retailers.
Most potteries refered to decals, etc. with numerical designations.”

http://www.ohioriverpottery.com/pages/decalline.html

“While you’re looking at the backstamp, look for dates, codes for
dates, or other indications of the age of the piece. Some dinnerware
was made for a long period of time. If having the older pieces is your
goal, you’ll need to be able to determine an approximate age of the
dish. Some backstamps include the date, but in other instances you’ll
have to determine the age by identifying the years the company used a
particular backstamp or other characteristics.”

http://www.suite101.com/article.cfm/american_dinnerware/81134

Other marks may include:

Throwers and Turners marks -- which consisted of a single letter
impressed in the clay, were added to ware to help identify pieces as
they were paid piece work.

Other Impressed Marks - include date and technical codes, often near
the footrim of ware (the base was stronger here) and these enable some
pieces to be specifically dated.

http://www.keithmurray.co.uk/backstamps/index.shtml

If you’re lucky (at least for identifying purposes) your dinnerware
will be a “name brand”  -- something easily recognized --  Some of
these would include:

Redwing
http://www.redwingnet.com/Gallery/Stamps_Logos/Stamps_Logos.htm

Royal Doulton 
http://www.raines.co.nz/doulton/doultonhistory.htm
http://www.tias.com/stores/vintage/tipsterms.html

Wedgewood
http://www.keithmurray.co.uk/backstamps/index.shtml

Rookwood
http://aarf.com/ferook97.htm



-----------  BOOKS -------

You may want to check your local library for either of these
comprehensive books –


Kovels' Dictionary of Marks: Pottery and Porcelain/1650-1850
Format: Hardcover, 636pp.
ISBN: 0891453652
Publisher: Collector Books
Pub. Date: December  1987

This dictionary provides a unique and quick way to identify American,
English, and European pottery and porcelain. The index of 5,000 marks
shows at a glance the geographical location and factory and family
name of the manufacturer, the type of ware, the production method and
color of the mark, and the date when the mark was used. 5,000 line
drawings.

http://search.barnesandnoble.com/booksearch/isbninquiry.asp?endeca=1&ean=9780517701379

Lehner's Encyclopedia of U.S. Marks on Pottery, Porcelain and Clay
Hardcover: 634 pages ; Dimensions (in inches): 1.89 x 11.38 x 8.66 
Publisher: Collector Books; ISBN: 0891453652; (March 1988)

http://www.amazon.com/exec/obidos/tg/detail/-/0891453652/qid=1031705220/sr=8-1/ref=sr_8_1/002-8099673-9238468?v=glance&s=books&n=507846#product-details



---------   SHOW US WHAT YOU’VE GOT    ----------

One final way to identify your dinnerware is to photograph (or sketch
accurately) the dinnerware,  backstamp and other details. Then scan
the picture into the computer and put it up on a website for someone
else to identify.

If you don’t have your own website, you can post pictures here: 
http://photos.yahoo.com/

If you were to do that, then post a NEW question on Google Answers
with a link to your pictures, someone would probably be able to
identify your dinnerware for you. Try to provide good clear pictures
and include your location (country) and any other details you know
about the dinnerware to help us narrow down the search.

Note:  I am NOT the person to do this as I don’t have the expertise or
the resources. So please don’t post that as a clarification to this
question. Let’s leave it to someone better qualified. Thanks.

So, that should give you a good start in identifying your dinnerware.
If anything I’ve said isn’t clear, feel free to ask for clarification.

-K~

Search terms:

Dinnerware identification
Backstamp stoneware
Backstamp pottery
Makers mark dinnerware

Also searched Google Images for: backstamp
http://images.google.com/images?sourceid=navclient&q=backstamp

Wow - more than I expected, and much quicker than I could imagine. 
Thanks so much. I had no idea this service existed until today - how
many other Dummies are out there like me??