An average tournament game is 300 points (and max 2 combat groups). It is highly adviseable to start at a considerably lower level in the first games. I'd say large games are 12-20 figures, any more and the reaction system overburdens you.
As I noted, it is a very different experience from many other miniatures games. I find it complements WM/H very well for me and scratches that sci-fi itch. The "special thing" about the game is its order & reaction system: every miniature you've got on the table gives you an order, which is either a combination of movement and some sort of action or a more complex movement/action. After a model completes the first action, if any of his opponents models gets LOS to it (or is within 8 inches of it), the model can declare an "automatic reaction order" (ARO) and do...something. This can be shooting, dodging, going to ground, climbing through a window, trying to hack his opponent's armour into immobility (if close enough or near a "Repeater" hacking extension device), jumping off a roof ledge...a long list. The active player then declares his second action of his order. If the two figures directly contest each other - like, they shoot at each other, or one shoots and the other dodges - they roll off against each other, with the active player typically getting far more dice (D20s). Highest roller wins, but it is roll under-or-equal to skill level (with modifiers, that make a lot of difference - range, cover, optical zoom on weapons, etc). If you are hit by enemy fire, you roll armour rolls against the weapon's strength to resist damage - but even if you succed, your model can lose his nerve and go to ground or jump back around the corner to avoid fire.
Oh yes, the rules are free:http://www.infinitythegame.com/infinity/downloads/rules/
...but sort of shoddily edited. There is, however, an officially sanctioned fan re-edit:http://members.iinet.com.au/~tenabrae/infinity/Infinity2_3_opt.pdf
I still thing the WM/H rules are the most solid thing out there, but Infinity, once you get into the game's internal logic, is really good as well and definitely rewards clever play. You need a lot of LOS-blocking terrain, though, or games end very quickly...even the bog-standard infantry, once there are enough of them (and especially if they are in Link Teams) can put out a lot of fire if you expose yourself.
What do you play, Crimsonsphinx? I'm proudly resisting The Man as the Nomads, myself:http://www.infinitythegame.com/infinity/en/category/nomads/