Lots of good advice in this thread so far. I'm kind of surprised that no one has mentioned Bjarne or Brebbia yet, though. Both companies produce fantastic smoking pipes. Out of the 10 Bjarne's I've owned, only 1 didn't provide a satisfactory smoke immediately, but it did eventually. I've owned two Brebbias, one cheapo ($45) and one Pura estate ($45). The cheapo had nice grain, was of an excellent size and weight for me (small), and provided an excellent smoke. The Pura, which would've commanded a much higher price new, provided the same excellent smoke that the cheapo did, it just looked a lot more attractive.
Bjarnes are no longer in production, due to the unfortunate death of Bjarne Nielsen, but you can still find them in a lot of places. Cup O' Joes, for example:
http://www.cupojoes.com/cgi-bin/dept?dpt=W&srch=DW&nitem=bjafsv09&tier2=59
If you want to go with an artisan, you can find a few members of this forum who make a great pipe for the buck. James from JSEC pipes makes a great smoking and great looking pipe for very little money. You might have to break the $100 barrier, but only just. His site:
http://www.jsecpipes.com/
I second the Boswell recommendation. I've never smoked one, but you can often find several on their site for under $100 and they have a stellar reputation for creating pipes that smoke perfectly. The only challenge is getting one before they're all snapped up for the week. The great thing is they post a bunch every Thursday. Their site:
http://www.boswellpipes.com/
Good luck on your search!