What game are you looking for a B-17 for?

There are a few B-17s here that will work but all of them are rather old.  Here's a list of a few of them (some aren't for FS2002 but they should work).

An F model here: http://www.simviation.com/fs2000vintage10.htm

another F: http://www.simviation.com/fs2000vintage11.htm

an E model: http://www.simviation.com/cfs2aircraft22.htm

a really old G model: http://www.simviation.com/cfs1aircraft4.htm (this one may work but its really old).

But thats really the only ones around.  Unfortunately there is a very large lack of B-17s in this hobby.  But here are a few you can try.