I started collecting stamps as a kid. I held onto my first stamp album for the longest time, but finally let it go when we moved in 2006. I was a pretty indiscriminate collector, and remain so to a degree.
When I got back into collecting in 2001, I tried to focus more on a few areas of interest: organs, music in general, trains and ballet (my wife worked at Richmond Ballet in VA for some years). As the children have gotten older and have developed a keen interest in fire fighting, rescue and police, we have together dabbled in collecting stamps related to that topic.
Topical collecting gets a bum rap sometimes from purists who think one should collect stamps by country or region. I understand and appreciate that opinion, I just don't follow it too closely. I do have a pretty substantial US collection, but nothing near completeness, and with none of the costlier rare varieties that distinguish a really fine collection. I also have stamps from many, many foreign countries, but nothing near completeness there either.
I house the collections on Vario stock pages in el-cheapo binders from the office store. I get stamps from anywhere I can, including my wife's office and my own, and a new issue dealer, County Stamp Center, in Maryland. You can also check out what dealer Alex Birman has on his mind about stamps here. The phrase "Scott #" refers to the cataloguing and stamp numbering system created by Scott Publishing Company and used in their print catalogues. I use a set from 2002. I keep my collections catalogued using Microsoft Excel spreadsheets.
If you have a question, leave it as a comment and I'll answer it likewise.