I was fixing my smokers with nichrome wires before I switch to resistors...I still have spools of nichrome wire in my shop...I used to buy my stuff on e-bay :http://stores.shop.ebay.ca/Wires-Store__W0QQ_armrsZ1.
Now if you put an Ohmmeter at the heater terminals of a stock H.L. smoker ; you will read around 18 Ohms ..This is the value you have to play with to calculate the lengt of your nichrome wire...Then comes the gauge of the wire..
For example if you want to use a 32 ga. nichrome wire...According to my seller ; a 32 ga has a resistance of 12.8 Ohms/ ft or 12.8 Ohms/ 12 "
So how many inches of 32 ga. wire do you need to get 18 Ohms ???
( I'm about to trow some algebra at you) 12.8/12 = 18/ x ; 12.8x = 12x18 ; 12x18/ 12.8 = 16.9 inches

So you need 16.9 inches of 32 ga. nichrome wire to have an 18 Ohms heater element in your smoker ...Well good luck to shove that in a 1'x1'x1' space...
Now the obvious solution is to choose a smaller gauge of wire ( like they did at H.L.)
According to my seller ; a 40 ga has a resistance of 81.7 Ohms / ft
if you do the calculations you will need 2.6 inches of 40 ga. nichrome wire to get 18 Ohms ( that's more like it )
The problem is that 40 ga. nich. wire is about the size of a humain hair ( after 10 min. of washing with head& shoulders)
It breaks when you look at it sideways...That why H.L. is putting so much cotton in their smokers that they"re full with 5 drops of oil...

But if you really really want to go with nichrome ...go for it ...It'll work but it's a lot more problems than resistors.

Oh ! by the way when I want to know how long my nichrome wire should be ...I just hold one end of the wire on the probe of my Ohmmeter and gently slide the other probe on the wire until I read 18 Ohms ; then I cut it 1 inch longer to leave room for the weldings...The hell with algebra