You can do most everything that is listed on that link with a good Random orbit 8" disc Sander.....I've got a Skill model 7490 picked it up for $40.00us @ Wal-mart came with a couple of sanding pads and a buffing bonet. Just don't cheap out on the sand paper spend the extra $2 for good 3M paper...It'll save you time and money in the long run. Use it for the heavy sanding to get rid of the anodizing (and the swirl marks) but when you get to wet sanding that's best done by hand with a sanding block (keeps you from taking all th paint off!)
The guy wrote the article using what he had...big beefy industrial stuff...But the same tecniques apply to your normal DIY tools too....and you can get the same resualts with a little more elbow greese and a little TLC with your tools!
(Note most of my power tools come from Harbor frieght and sears....and I'll try anything! once....If I like it I'll do it again!)
You can cut curves and pretty much anything with a jig saw....I'll have to post some of the other case windows I did....All the cut was with a sears jigsaw, and I cleaned them up with a Dremel sanding wheel! It really comes down to what your comfortable using... and How good you are at using it.
Heres a good hint all ways cut it 1/16-1/64 smaller than you plan when cutting out a side panel....cause if it's not perfectly smooth you can file it down to the line...if it is perfectly smooth no one will notice 1/64 of an inch!
Crazybillybob