Welcome!
This model is known as the E46 family, they were made from 1999 thru 2005/2006. In general, they are good cars. Looking for a manual transmission is good, some feel that the weakest part on BMWs is the automatic transmission.
If you are not buying it from a BMW dealer, you should strongly consider taking it to a BMW dealer for a presale inspection. They will charge $100 - $150, but you get a written statement of things that they consider need work, problems, etc. If the seller won't let you do this, they probably have something to hide.