True. Every, every flash will work with any camera as long as the camera has a hotshoe. If it has a PC sync connector that's even better (you can connect flashes to it directly by sync cord - if the flashes have the sync port, of course).
The flashes usually don't have a PC sync connector (some do, mostly Nikons and some Canons (as the 580EX, for example), but you can buy an adapter that converts the hotshoe to a PC sync port.
You can for example buy three receivers and one transmitter, put the transmitter on the camera hotshoe (or connect it to the camera PC sync), put receivers on flashes (via hotshoe directly or hotshoe adapter (depends on the model of trigger)) and that's it.
I reccomend you take a look at Lighting 101 on Strobist. Great stuff, let me tell you:
http://strobist.blogspot.com/2006/03/lighting-101.html.
And do a search query on the Strobist discussion group on Flickr regarding the best eBay trigger (probably the 16 channel version or the 4 channel one (ver 2.0)).
I personally don't use them, 'cause I know that they can be unreliable, but some say they work flawlessly. As for me: I chose the Canon wireless way to retain e-ttl compatibility, but I'm probably soon buying radio triggers as well (in that case you have to use flashes manually, but that's not such a big problem after all).
Hope it helps, man. Before you do any purchases I beg you to read all the available resources on Strobist. I don't want you to curse me if something goes wrong;)
