Is there a site to lookup part# for various GM parts?

[2QUIK6]

I always find myself trying to find a part number for something to lookup the price on gmpartsdirect.com. The only way to find parts on the site is by part#, and I can never locate the part# without going to the dealer usually. I know there's several places to part Turbo Regal part#s, but this is for my Silverado truck.
Thanks

 

[Harry Mash]

http://rockauto.com/ This parts store usually lists the GM#

 

[2QUIK6]

Originally posted by Harry Mash
http://rockauto.com/ This parts store usually lists the GM#

I've been using that one, its the closest thing to a parts lookup that I've found, but like you mentioned, sometimes they don't list the GM # or the one they list comes back as an invalid part# for gmpartsdirect.com which is the case for an AC blower motor I'm looking for.