Depends which units you are after. Most British troops will double as "ripe" (ie red coated) Loyalists; I can't think of anyone offhand who makes Volunteers of Ireland, but most ranges will include Queen's Rangers infantry.
I forget the exact code numbers, but the Minifigs "Continentals in Floppy Hats" and "Continental Marines" both make excellent Provincials.
Look here for size comparisons and a check list of who makes AWI:-
http://www.deepfriedhappymice.com/html/awi.html
Just be aware that the artillery have been "up next" for a few years now.....