I would highly suggest that you choose a name brand laser for your first unit. while it is true that dx has some cheap lasers, that's just what they are - cheap lasers. You can buy one if you want, but be prepared for it to be unreliable and perhaps DOA. Also, im not sure what the import limitations on DX are, but i've heard that customs has been cracking down on them, so you may not be able to order from them at all.
You can get a laser-wave 100mw greenie for $250 though CTlaser (gottaluvlasers here on PL). For that power and that quality $250 is a very nice price. if $250 is a humbling number, I would suggest you start with diode lasers. if you check out the laser pointer forum you can find group buys on 16-22x dvd burner diodes that will kick out a couple hundred mw each. if you combine these you can get a red 650nm that will easily do 250mw for $100-$150. you can also do the same with Blu-ray diodes.
Dr.lava on here sells the flexmod driver, which is what you'll need to drive the diodes, but for it's price it is an impressive piece of kit. he sells the flexmod (As well as his other drivers) here:
http://hacylon.case.edu/ebay/laser_diode/FlexMod01.php
In addition to that, you can check out the buy/sell/trade section of this forum, and you may find some good deals on used lasers there.
Good Luck, and welcome to the forum!
"TO DO IS TO BE" - Nietzsche
"TO BE IS TO DO" - Kant
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