Where did you install m4? Check it's in /usr/bin
On a side note, can you copy and paste from a .pdf file? I've had good results working from html as I can open it in Firebird and copy it into a terminal. It helps to avoid typo errors. That's why I find the hardest part of Linux From Scratch is starting Beyond LFS as it's all at the command prompt with no Firebird till I get X windows (and a few other things- gtk2) up.
Go back and re-do M4. Check you havent installed it in /ussr/bin or /ur/bin something. Typo errors can really screw you up. Try
Then make a temporary folder in your home directory, untar a fresh copy and configure it with --prefix=~/tmp and install it in there. That way you can see all the files it's installed which makes it easier to hunt down whatever you've installed in the wrong place, if that is the problem.