Have you tried PDF-XChange Viewer? It’s a free app that I’ve used to fill out PDF forms and save them. Just be careful that you get the right version. This company has a number of other paid pdf products. It can even be used for commercial purposes without paying for a full license.
Foxit Reader (free) can both fill out pre-made fill-able PDF forms, & also can use the typewriter function to write on an existing (non-fill-able) forms, & save same – without watermark.
“Foxit Reader 4.3”
If you aren’t able to go with the paid Adobe Acrobat solution, you should check out CutePDF. http://www.cutepdf.com/Products/CutePDF/writer.asp its freeware for non commercial use only.
If a PDF has fields designated as input forms, you can use Adobe Acrobat Reader to type in the fields. Once done typing you could print it and re-scan it.