You can fill out pdfs with flpsed. flpsed allows you add text to pdfs.

flpsed - a WYSIWYG pseudo PostScript editor

On another note xpdf is many times faster for small pdfs than acroread. However, if you zoom in on a big pdf (like a map) w/ xpdf it renders the whole thing to X as an image. If that image is bigger than your memory (regardless of the screen size), X swaps out and your machine is reduced to a crawl. Acroread, on the other hand, doesn't do that. It just renders the part of the screen that is visible, which is slower than keeping your image in memory, but much faster than reading swapped contents from disk.

Kludge