Welcome to werkz and to BMW ownership
There is a lot of 'tips 'n' tricks' info on the E46 section of the site: http://www.bimmerwerkz.com/forum/3-series-e46-e90/
(lol -- I just checked... we actually have a stickied thread called "E46 Tips And Tricks")
In general, you have acquired a very solid car. If you have any technical question that you can't find an answer for on our site, feel free to start your own thread and more often than not, sombody here will be able to point you in the right direction.