I recommend you first take a look on battle reports to have an idea of what the battles looks like
http://sg.tacticalwargames.net/forum/index.php?board=60.0 Now my 2 cents:
1. There are a wide varity of other manufacturers cheaper than GW that you could use to building up an army
here I give you a list of manufacturers. There is other information in spanish, you can ignore it and go straight to the links
Copplestone Castings. 5,35£ (infanterÃÂa 6x5; caballerÃÂa 12: arqueros 12x2)
http://www.copplestonecastings.co.uk/Chariot miniatures. ?
http://homepages.ihug.co.nz/~firefall/chariot.htmEureka Miniatures. 13,50 AU$ (infanterÃÂa 30; caballerÃÂa 15)
http://eurekamin.com.au/scale10mm.phpGames Workshop. 12,50€/ 8£/ 15$ (infanterÃÂa 6x5; caballerÃÂa 6x2; 12x2)
http://www.games-workshop.comGFI (Minifigs). 6,95$ (infanterÃÂa 24; caballerÃÂa 12)
http://minifigs.com/catalog/GHQ (Micro Force). 7,95$ (infanterÃÂa 26; caballerÃÂa 12)
http://www.ghqmodels.com/store/n-scale-model-railroad.htmlIrregular Miniatures. 15p (infanterÃÂa 1); 30p (caballerÃÂa 1)
http://www.irregularminiatures.co.uk/Kallistra. 5£ (infanterÃÂa 8x4; caballerÃÂa 16)
http://www.ghqmodels.com/Langton Miniatures. 4,50£ (edificio 1)
http://www.rodlangton.com/starfort/10mm.htmMagister Millitum. 5£ (infanterÃÂa 30; caballerÃÂa 12)
http://www.navigatorminiatures.com/prodtype.asp?PT_ID=3&strPageHistory=catMusket Miniatures. 6,95$ (infanterÃÂa 24; caballerÃÂa 24)
http://www.musketminiatures.com/Obelisk Miniatures. 5,50€ (infanterÃÂa 30; caballerÃÂa 15)
http://www.obeliskminiatures.com/Old Glory Miniatures. 9,50$ (infanterÃÂa 50 o 30); 16$ (caballerÃÂa 30)
http://www.oldgloryminiatures.com/categories.asp?cat=10Pendraken Miniatures. Histórico 3,25£ (infanterÃÂa 30; caballerÃÂa 15), FantasÃÂa y Sci Fi 1,45£ (infanterÃÂa 10; caballerÃÂa 5)
http://www.pendraken.co.uk/index.htmlSteve Barber Models. 3£ (infanterÃÂa 20; caballerÃÂa 10)
http://www.sbarber-models.clara.net/main.htmlStone Mountain Miniatures. 3,95$ (banderas de papel 1hoja)
http://www.historicalminiatures.com/flags10.html#EnglishTB Miniatures. 5,28€ (infanterÃÂa 24; caballerÃÂa 12)
http://www.tridentebologna.it/miniature_E.php?epoch=2Warrior Miniatures. 60p (infanterÃÂa 10)
http://www.warrioronline.demon.co.uk/10mm/index.htm2- For beginners and slow players and quick battles I recommend 1000-1500 points per battle. I use to play that way.
3- Depends a lot of the manufacturer you go. Gw is like doubling the price. Count that an army is between 10-15 units (depends chaos needs less units that undead). For GW a blister is 12 euros.
I feel really pleasant to use cav with the half of miniatures per unit. You get for a blister 2 units, and the bases are more dynamic and you could enjoy better the paint. It is up to you.
4- Yep I think you can get an army to start with and have a lot of fun
5- The rulset is superb. I do not find yet another system better than this.
6- I find 10mm and 6mm perfect scale for warmaster system. and to evocate a real battle.
7- Battle of five army is a great game to play. Also the minis are easly transported to other armies. I recommend it, (I have to set of battle of five armies)