Here's a
link to a Porsche forum that shows a cheap toe gague and how to use it.
I do my own toe alignments using the (borrowed) deluxe version of this tool, but at the price they're discussing I may run off to HF to get one of these.
Only caution about it is that you have to bounce the front end a bit and roll the car back and forth some feet to get the adjustment settled between measurements - or get four hardened, ground and lapped steel plates with grease between them, a pair each under your front wheels to be glide bearing for your front end.