Try the Munton's Premium American Style Light Beer. Order it from Austin Homebrew Supply and get their canned kit upgrade and you'll be in the ball park with a beer that will be similar or better than Miller Lite. If you want to try and match Miller Lite more perfectly, instead of the canned kit upgrade try in the neighborhood of 3/4-1 kilo of Dextrose. That kit will get you very close to Miller Lite, just make sure you ferment it as cool and clean as you can, 50F works great for me, and try to avoid adding anything that will all any kind of flavor - stick to dextrose and you'll be darn close.
Another kit you might try is Cooper's Draught - that beer is spot on Miller Genuine Draft when made with a mixture of Light DME and Dextrose. I bet if you take it very gently with the DME or leave the DME out entirely and go for just dextrose you'll be right in the neighborhood of Miller Lite too.
Should be well within your means to brew either one of these kits, I brew one of these just about every month - I like Light Beer too.
Light beer is kind of hard to brew, because most of the advice you get on this forum is advice for making beer snob beer, and not a beer like Miller Lite. The trick to making a light beer is just avoiding a few ways you can easily go wrong... don't use anything that will add a flavor, no extra malt extract, no steeping grains, none of that. No extra hops. Don't try and bump the alcohol up.
If you've got to tamper with the instructions on the kit and not follow them, then invest a couple extra bucks in a real lager yeast.
Ferment the beer at an appropriate temperature - lower 50s with a Lager yeast and you'll have something very much like Miller Lite.
You can buy a 30 pack of Miller Lite for $15. Why would you want to brew it at a greater cost?
I don't know - maybe he likes to brew ?
