Then you might consider getting it professionally recorded.
Yes.
That too. Among many other things, probably.
Yea. First, I'd recommend paying a visit to the "Studio Building" forum. Scroll down towards the bottom of the BBS (towards the dragon cave), and look through some of the posts . . . search the archives . . . maybe post a question or two about how to sound treat your recording space. Look for terms such ass "flutter echo," "early reflections," "diffusion," and "bass traps."
That should get you started. The idea is to learn about the role your room accoustics play and how they affect the quality of your recordings.
Then go get yourself a good, high-quality mic, a similarly high-quality mic pre, and run all of that in to a decent a/d converter. You'll also want to pick up a good compressor that fits the kind of vocals you want to do. A good parametric equalizer is also a very good idea. This is going to cost some money.

But you did say you wanted it to sound like "a professional recording," and most professionaly recordings are done using some fairly high end equip. There are some exceptions, but they're few.
For ideas and opinions on what brands / models of toys to purchase, I'd highly recommend using the search function on this board . . . or better yet do an advanced "Google Groups" search with "rec.audio.pro" as the group. There's also a great forum at gearslutz.com. Very good info to be garnered there.
Of course you'll want to spend a good chunk of time breaking in and learning how to use all of your new toys. Practice is very important -- might be a good idea to set aside the next couple years recording yourself and other bands to get some practice in. Again, if you want your stuff to sound "like a professional recording," then it might also be a good idea to try and get a few years in as an intern with a recording engineer who knows his stuff. Crappy hours and no pay, but you'll learn some tricks.
Good luck.