[Help me start my collection...]

You seem to have series 1 foils, so

 

series 2 human torch, namor, thing, dr doom

series 3 thor, ghost rider, magneto ,wolverine

series 4 elektra, punisher, daredevil, beast ,goliath, gambit

series 5 red skull, mr fantastic, silver surfer, sabretooth, colossus, nick fury, blade, * spain exclusives

series 6 phoenix, cable, juggernaut, deadpool, wolverine, punisher

series 9 war machine, nightcrawler, hulk, bullseye, professor x, deathlok, dr strange * canada exclusives

series 10 spiderman, angel, black panther, mystique, omega red, cyclops, mr sinister

 

most of the foils are gold, but later foils gained colors, red, blue, silver, and grey

 

I have a complete set of foils, but unfortuneally not for sale, Some are extremely hard to find ...good luck on your quest.

 

Also the variants have same foil as regular figures: Series 1 yellow IronMan is same as Series 1 gold IronMan