dealextreme sells lasers at great prices, but i've heard of many of them dieing prematurely, or not having great output, it's a bit of a gamble as part of the reason for the very low prices is that they're very cheaply made. nova lasers is great for cheap *good quality* lasers, with their X series (even better with the 5% LPF discount). if you end up going higher end, optotronics and laserglow both have great reputations and great lasers, laserglow always seems a bit pricey to me, though they do seem to have a greater range of stuff. welcome to LPF, anyway!
If you are wanting a laser from 15-125mW, about everybody here is going to tell you to go to Novalasers.com. I have the 105mW version of the X series from them and it is a great laser, they have a reputation of sending out overspec lasers!