I'd love to register a .bit domain just as an experiment/for fun, but I'm a bit wary of the methods for obtaining bitcoins that I've found.. anyone have a good tip for an exchange, or experience with obtaining bitcoins/registering a .bit domain through any other means.. Or, any other related information to share?
I also can't quite figure out if it's worth my time to set one of my computers at mining bitcoins, how long should I expect it to take me to mine enough to register a domain?
The short answer is that you SHOULDN'T set up a mining rig to mine bitcoins, if all you want to do is USE bitcoins.
Simply buy or trade for them. The easiest way to do that, in my opinion (from a US-centric perspective) is to set up a Dwolla account, transfer a bit of money from your bank to Dwolla. Then transfer that money from Dwolla to an exchange (Mtgox and TradeHill are two examples), and then buy bitcoins at market rate.
Then you can use them to buy goods and services (including namecoin names). Bitcoins are the "currency". Namecoins are sort-of related (using the same underlying technology), but are a separate product.
Namecoin is based on Bitcoin, but it uses a different block chain. Essentially, they are two different "commodities". You have to obtain namecoins in order to purchase .bit names.
Also, to answer your question, mining is really ineffective for home users. I mean, if you have energy to waste on it, that's fine, but you'll find it's more economical to simply buy the bitcoins through bitcoin exchanges (Tradehill, MtGox) than it is to mine them.
I also can't quite figure out if it's worth my time to set one of my computers at mining bitcoins, how long should I expect it to take me to mine enough to register a domain?