Are you running the 32 or 64 bit version of fpc/lazarus. I found that most of dbconnectors do not appear on 64 bit version. I switched down to 32 bit and they were all there. If anyone knows how to get the mysql 4.0, 4.1 or postgres connectors and sqlite3 to compile in the win64 bit version of lazarus please make a very loud shout out.
jonathan