1) I need a good glossary of piping isometric terms commonly used in
the oil/gas plant construction industry
2) A book at technician level explaining isometric drawings, symbols
and circuit interpretation

Hi derek_hv,

After searching for quite some time, I've not been able to find an
online glossary specific to your field. However, I did have some
success finding a few books and one video. Please have a look and let
me know if this would satisfy your request. If not, hopefully another
researcher will have better luck.

Sincerely,
hummer

BOOKS:

Pipe Drafting and Design (Parisher/Rhea):
Chapter 13 Piping Isometrics
What Is an Isometric?
Drawing Piping Isometrics
Isometric Dimensions, Notes, and Callouts
Isometric Offsets
Review Quiz
Drawing Exercises
http://www.pipefitter.com/pipedraft.html

$43 on Abebooks, new copy:
http://dogbert.abebooks.com/servlet/BookDetailsPL?bi=205399924

Pipe Drafting and Design Workbook (Parisher/Rhea):
http://www.pipefitter.com/pipedraftwb.html

Process Pipe Drafting:
Chapter 8 Piping Isometrics 
Isometric Layout
Drawing Isometric Offsets
Calculating Isometric Offsets
Isometric Dimensioning and Labeling
http://www.technicalbooks.net/Merchant2/merchant.mv?Screen=PROD&Store_Code=1&Product_Code=GW75355&Category_Code=13050

The Pipe Fitters Blue Book (Graves):
http://www.pipefitter.com/TPFiB1.html

Pipe Fitter's Math Guide (Hamilton):
http://www.pipefitter.com/pfmg.html

Focused on Piping Design Books and Publications:
http://www.pipingdesign.com/books1.html

VIDEO:

Part 10: Piping Isometrics
What is an isometric, piping isometrics, isometric drawing symbols,
isometric dimensions, isometric notes and callouts, isometric offsets,
multiple angle offsets, rolling offsets. 53:00
Videotape Purchase: Order BP40, $225
http://www.firstgroupcom.com/drafting/pipe-draft.htm


Here are some glossaries that I came across - I'll include them here
in the outside chance that one of them will click.

Piping Glossary:
http://www.svminc.com/Content/Department/Piping/PipeGlossary.html

National Piping Mapping System Glossary:
http://www.npms.rspa.dot.gov/aboutnpms/glossary.htm

Glossary:
http://www.tpub.com/blueprintreading/49.htm

Glossary:
http://www.setlaboratories.com/glossary.htm