Are you sure that you want to record with a computer? You said that you want professional recordings.
If you are dead set on getting a computer to recorder with then here are your answers:
1. Plan on getting an apple laptop. Which imac would be best. Laptop or desktop? apple or microsoft?
Get a desktop.
Apple is fine if you plan to use Pro Tools.
2. Software? I hear a lot about pro tools?
3. If I were to buy pro tools, is that all the software I would need?
Pro tools is all the software you need.
3. If I buy protools, do I need preamps?
You will need some way to get the signal to the protools interface (preamps or mixer)
4. Mixers or Firewire intetfaces?
I also recommend an external hard drive.
5. When recording with computers, are there a limitless amount of tracks to record on?
Yes and no. The more tracks you record on a song the more processing power it takes.
Just like with analog tape, computers can make bounces of tracks to free up more tracks.
If you are open to suggestions about your recording equipment then here are your answers:
1. Plan on getting an apple laptop. Which imac would be best. Laptop or desktop? apple or microsoft?
Don't waste your money on any of these items because they have nothing to do with professional recording and they cost lot of money.
2. Software? I hear a lot about pro tools?
I'm sure that you don't hear that even Pete Townsend, who is partially def, was not satisfied with the downsizing from 192khz to 96khz and opted to run the signal from the analog outs of the Pro Tools to Genex converters when producing the "Tommy" DVDA-SACD hybrid project.
3. If I were to buy pro tools, is that all the software I would need?
It is if you want to give in to today's manufacturer's theme, which is "higher profit margin outways superior sound."
3. If I buy protools, do I need preamps?
Oh boy. Notice how the market is flooded with tube preamps, analog simulators, noise generators, etc. What do you think they are telling you? They are saying that they know that digital recording is not all that it is made out to be so here are some half ass fixers that might help your situation.
5. When recording with computers, are there a limitless amount of tracks to record on?
It may be limitless in the amount of tracks but it is limited in the amount of information. The computer translates the signal into code (ones and zeros). If there is too much information then it will take an average, or round off, or sometimes even zero out. On the other hand if you get an analog reel to reel recorder, the magnetic tape will hold a full analysis of the freqencies because it has no other choice. The changes in voltage are what they are and not anything else.