D3D,
Pauly here is a really good guy who has worked for literally years fighting to get good color off of an Oce Arizona printing on glass with Onyx. He's been on just about every forum on the Internet searching for answers, and I'd wager has spent well into the tens of thousands of dollars on hardware and software alone, let alone his time and materials. Just having read his posts on other forums over the years, if I had to put a total value on his pursuit of color profiles, I'd put it at north of 50 grand.
So I'd keep that well in mind as you go looking to get there on the cheap.
Fact is, I can guarantee you that the cheapest way to where you want to be is me. Because I get you there, on the first try, and then that's the end of it, and you put it to work and start making money.
Not to mention that you also then get free lifetime tech support. So if you do have any issues, you call me, not cast about on the Internet and get answers from people who may or may not have the slightest clue what they're talking about.
A couple other things: The poster that said you can't profile with Rasterlink is correct. You'll need some other RIP if Rasterlink is what you've got. Pauly is also right that I tend to prefer Onyx, but not always and not in all situations. I am an Onyx and Caldera dealer, so I could point you in the right direction if you also need a RIP.
Also note that you cannot make a backlit profile with an i1. For that you'll need a transmissive spectrophotometer. They're not cheap.
One thing I would quibble a bit with Pauly on is that I would beg to differ that the way to get the very best profiles is to invest a huge chunk of your time and money in software and hardware and self-teaching to learn to make two profiles yourself.
Fact is I profile large format printers for a living. Large format color management is all I do, and I've been doing it for 11 years. In that time I've seen, worked with and profiled just about every RIP, printer, ink, media, and process combination out there. There's no way you're ever going to duplicate all the knowledge gained from that kind of experience on your own while you tend to everything else that goes into running your business.
And myself, I just can't imagine why anyone would want to.