I shoot architectural on a semi-pro basis. I use a digital back on a Linhof M679cs for most of my work, but also a Canon DSLR with their T&S lenses, and sometimes a digital back on a Hasselblad Flexbody. Given that you're just strarting and money's tight I'd recommend a Canon 5D with the 24mm and 45mm T&S lenses.
Firstly the commercial architectural market is now overwhelmingly digital based, that's what most of your likely customers are geared up for and what they expect. Sure, there's a "fine art" architectural sector where film still plays a role (I use 6x9 film myself on occasion), and film may have a place away from the big cities, but basically digital is becoming the new standard. And that means delivering an un-rezzed file capable of 300dpi across a double page spread. You're in that territory with a 5D. It may not be quite as good, nor quite as flexible, as a digital back on a technical camera, but it's close enough that great execution will overcome any technical shortfalls.
Secondly, outside the hobbyist/fine art end of architectural most of the shots you'll take will be interiors rather than exteriors, certainly that's the case if you expect to earn a living from architectural work! And it's with interiors that the digital advantage becomes clearer. Colour temperature balancing, mixed lighting, huge light-to-shadow ranges, all these are a lot easier to deal with when you're working with digital. And digital's a lot cheaper too, I found with film that my largest equipment expense, and by far my largest luggage item, was lighting. Remember, you'll need an assistant and the means to be independent from mains electricity with most film lighting set ups. Increasingly I find I can handle most interior shoots single-handed, with only a pair of Canon flash guns, when I'm using a Canon DSLR and Photoshop.
Thirdly, at least here in crowded Europe, shooting exteriors often means extensive retouching to remove road signs, street furniture, inconveniently parked cars etc. This is a lot easier and a lot cleaner, when you're working in an all digital environment.
So, my advice is a 5D, 24mm and 45mm T&S lenses, Photoshop, a polarizing filter, a Canon flash with remote triggering cabability, a couple of large white reflectors and a couple of light stands to hang them on, and you're in business!