I've been with a bazillion hosts over the past few years with various businesses, and so far, we've been totally delighted with servermatrix.com, which is a division of theplanet.com. Inexpensive, plenty of bandwidth, very responsive on service.

But I also have heard fabulous things about Chilihost.

A lot also depends on how tech savvy you are... Servermatrix isn't a good choice unless you're comfortable installing scripts and handling most basic maintenance issues on your own... part of the reason it's so inexpensive is the pricing assumes you'll be your own sysadmin. If you can handle that, you can save big bucks by taking care of it. Otherwise, it's false econonmy to buy on price, because a couple hours' downtime can cost way, way more than the cost difference for a month.