Mitch, worry more about the pre-amp. I have a cheap Samson Q2U that sounds great through a decent pre-amp. You don't have to spend major coin either. I use a dbx mini pre-amp, but they no longer are made. Have yet to read a negative comment on the VTB-1 recommended by rharv and others.

The room and acoustics of the room that you will record in will matter as much or more than the mic, particularly if you go for a condenser of some type - they simply have too broad of a pattern to ignore the room. A good ol SM 58 will reject most of the room effects however. SM 57 is just as usable - pop filters are nearly free for them.