Last year, a friend and I put the whiskey barrel I bought to good use and brewed an imperial stout designed to be aged in said barrel. The recipe was, to say the least, intense. Easily the most expensive beer I have done to date, using a TON of specialty malts and in the end (thankfully) tasting comparable to Firestone Walker's Parabola, but here's the thing: It might also be the most delicious beer I've ever done. It's certainly the prettiest:
Looks wonderful, doesn't it? That's my co-brewer in the photo, and the beer is just a few weeks old (after a long primary and then secondary in the barrel). If you want the recipe, just ask. It's extract with specialty grains, so anyone can make it.
After the imperial stout, I did a honey porter in it, and the barrel currently contains a lambic, which will stay in the barrel for about a year or more. My plan is to blend small parts of that batch into future lambic and sour batches. (I currently have seven vessels with various sour beers, so the blending opportunities are endless!)
So here's the thing: Barrel-aging your beers is easy.
1) Buy a barrel! Just Google various phrases, there are TONS of sources. Spend between $70 and $120 (before shipping) for a 5-gallon barrel or you're getting ripped off.
2) Don't worry about cleaning it out. All that booze will keep it sterile. Just brew a big beer and put it in the barrel!
3) How long to age it? Keep the beer in it from two weeks to two years, depending on the beer. A weeks to two weeks is great for IPAs and Double IPAs, two to four weeks is ideal for traditional stouts and porters, four to eight weeks for barleywines and strong Belgian styles, and a month to two years for lambics.
4) Bottle, age, open, enjoy!
Yeah, seriously, it's that easy. I recommend bottling a few smaller sampler bottles so you can taste it over time -- barrel-aged beers tend to need some time to age into perfection, about six months to a year in my experience -- and going easy until it has aged into your taste. After that?