Good crimpers tend to be expensive because the dies must be precisely machined and it requires a lot of force to make a good crimp. The wire is actually cold welded to the contact and held more securely than a soldered joint. A good crimper will grip the contact securely, then crimp the wire and as the die moves, it will also crimp the insulation if the contact has an insulation holder.
I haven't used this particular crimper: http://www.hansenhobbies.com/products/c ... /crimp_dx/
but I've heard it works well. It's about $40, which is a better price than many: there are manual crimping tools that run close to $1000.
Adafruit carries this one that looks well made: https://www.adafruit.com/products/350
and there's a tutorial on using it.
If you do get either, please report back. I'm thinking of purchasing one for a spare, but have yet to get around to it.