Here's the problem.  I have a spreadsheet with names of companies. 
One of the columns has the 2005 Fortune ranking.  I'd like to update
this to the 2006 Fortune ranking, but I don't want to do it manually. 
(I have a spreadsheet with the company name and ranking).  Thus I'd
like to see if someone could write a program that would somehow update
this information.  The column currently says, for instance, "#105 on
2005 Fortune 1000".  The new spreadsheet simply has a column with the
company name and another column with the rank (ie, 106).  As to my
Google Answers question, I'm looking for a website or forum where I
could find someone to do this.

Try this board http://www.mrexcel.com/board2/viewforum.php?f=2 It is
full of very bright Excel experts.

Am i understanding this right?
-You have a spreadsheet that needs a set of data replacing.
-The new information you want to put onto the sheet is in another spreadsheet?


If this is the case all you need to do is copy the worksheet with the
information on into the other workbook. (You can then hide this
worksheet if you want)

Right after youve copied the work but go the worksheet that you want
the information on and click the first cell in the table. Click "="
then click the worksheet with the replacement data. Click the first
cell in the table and click the enter key. This should take you back
to the worksheet that you want the new information in. The use the
leaver to drag rest of the information into the other cells. (Click
the bottom right of the cell until the cursor changes to a plus sign.

I hope this helps, if i've misunderstood the situation please post a
reply and I may be able to help you further.

IF the name of the companies are identical in both the spreadsheets
then  a case a comparison can be done in a loop and beside the company
name the position can be placed or beside the position the company
name can be placed. IF this does not solve the problem then take the
last worksheet and sort it according to position.

If the company names are the same, you can just use vlookup, something like

="#" & vlookup(a1,"sheet2!A:B",2,false) & " on the 2006 Fortune 1000"

where a1 is the cell containing the company name on the sheet
sheet2 is the 2006 sheet with column 1 containing the company name and
column b the ranking.

Then just copy the formula down to each row.

just to re-like what 'matthelliwell' said..
vlookup is the best way of doing it..