As above: the only way to get a color-correct workflow is to use a hardware calibrator and a high-quality monitor and printer. You have the printer. Buy the calibrator (as mentioned, this comes up regularly), and think about saving for a better monitor than the MBP display gives you. The Retina (™) displays are certainly usable, but are (IME) much better for watching movies than for editing photos.
Use the mfr's ICC profile for whatever paper you like. It is not likely, imho, that you will ever need to make your own profile or have one made.
Learn how to soft-proof.
Upgrade your software. PS CS3 is old. (I don't know if it is out-dated.)
The ICC profile is usually selected in the printing app's print dialog. The paper (often called the media) is selected in the printer's print dialog. There are usually two print dialogs invoked when you print.
Since you are on the OS X platform, you might consider purchasing Aperture, even though Apple just announced they will not support it beyond making it work with their up-coming OS, Yosemite. Aperture is unsurpassed as an Image database, and has good color, proofing, and printing controls. It should be usable for about 18 months.
While I wouldn't want to take any earnings from a guru, I suggest learning how to use and trouble-shoot your equipment yourself. The transition from digital media to physical media is fraught with pitfalls. You will regularly fail to get the results you want, and will want to be able to rely on your own skills to trouble-shoot. Printing is not a "set it and forget it" process.
Your goal — "soon get to a point of high quality predictable results with 1 or 2 papers
" — is easily reached with some effort. I recommend using Epson Fine Art papers — they are good, they work, they are readily available in all popular sizes and types — until you are comfortable printing.
When I was learning these things, I found the information on this site (Luminous Landscape), and on Cambridge in Color
Good luck. With a photospectrometer, a MBP, and the 3880 you should be making impressive prints soon.