weighting of lures

[crankybait]

what difference does weight make in a lure, besides castability. also, does placement of the lure matter so much? im looking to buy some lure weights for the lures im making from here http://www.lurehardware.com/Lure_Har...e_Weights.html

but the smallest is 2 grams. and most abits i see are around 1/2 gram. so im wondernig if it will matter. and if you have any better ideas, please tell me so i can make an order so i can make more baits, because i tried casting an unweighted balsa weight and it went perhaps 2 feet at most. these weights ont he site i posted have a line tie, but im thinking their diameter is so big that it would be hard to put into the nose, since the nose could be narrower than the weight.