I have Alenco Windows in my home, one has a bad seal (moisture around the edges), the other has a stress crack. How long is the warranty and who do I call to repair them?

Here's a copy of the warranty. They offer 1 year on most of the window, 10 years on the glass seal.

Link to Alenco Warranty (PDF file, Acrobat reader required)

The claims address is in the warranty. You can probably also contact an Alenco dealer in your area.