I'm not sure about those particular model numbers on the alpines, but if it is coming with 3.5" coaxials and 6x9's along with that lower end alpine deck you aren't getting a great deal.
What I would do is go to your local car audio shop and listen to component speaker sets to decide what you like. Everyone has different tastes, but you can get a **** nice set of components, to your taste, for $600. Check out brands like Diamond audio, Dynaudio, Rainbow, Focal Utopia series, CDT Eurosports, all make top of the line component sets.
Once you find what you like check on the internet and see if you can find a reputable store that sales the kind you like. You pay big premiums if you buy from the store.
A very nice alpine head unit is the 9815, check the stores though and see if some of the other brands may have more of what you're looking for. The 9815 runs about $350 off of
ebay.
You will want an amp for your components, you want an rms rating a little over what your components rms is rated at so you can have some head room with the power. You can buy a nice US Acoustics 100x2 amp from thezeb.com for $100, something along those lines will work great. If you're really wanting to spend the whole $3000 you can get into a zapco reference 350 for around $450.
The next part is dependent on what you want your system to do. If you want a really loud system you could go with something like a Resonant Engineering 18" XXX or 18" MT. You can pick the XXX up for around $600 I believe from respl.com (don't quote me on that). If you are looking for sound quality that can get loud I would check out Elemental Designs A series or a Stereo Integrity Magnum D2, stereointegrity.com--I personally own this sub and love it. You could pick up two of either of those for around $600.
You will need an amp for your sub. Either way you go 2000 watts will play those subs very well. A Tsunami 1800 or 2 pic 880.2 will work well and both setups go for around $400 total.
You will need wiring and a box, say $100 for each, wiring wont be quite that much but we'll round up. Sound damping is another good one which will be another $100 or so.
You could very well end up needing a new alternator and battery for your amp(s) which will run you in the neighborhood of $300.
Let's tally it up:
Head Unit: $350
Components $600
Component amp $450
Sub(s) $600
Sub amp(s) $400
Wiring $100
Sound Damping $100
Sub box $100
Amp and battery-$300
Total comes to...$3000 on the nose
Hope this helps a little bit. Good luck.
Mike