ok so I think you have missed a lot than my new tama friend ^.^ the list from v3 and up is:
v3 of course!
v4
v4.5
v5
v5.5
v6 music star
v7 also known as the tamago
TMGC+C first color tamagotchi on the scene (vintage now, so your looking at around $128 for NI
tamagotchi ID (very cute and very expensive, hard to come by cause of course vintage
tamagotchi id l and/or tamagotchi id le which ones Japanese version your looking at average of $50-$80 on the idl but the id le is another story that ones English and VERY hard to come by as only so many are made and sold only in Tokyo these go from $150 upwards to $248 at times..depending on color etc
now the newest on the scene and my personal favorite! is the tamagotchi p's you can get it on average for $55- $89 there are tons of colors to choose from not too mention there are limited edition sets out too...
these tama's are much for complicated as they have so MANY new features! they also have whats called deco pierces that hook into the tama p's and unlocks characters and features that can only be obtained through buying those deco pierces...I have all of them and they are worth the money!
now since your just coming back into the scene I would say start with a tamago at the most if your wanting to jump inot the color tama's cause its not in color but its the introduction of the newer features then work your way up <3
I hope this helps a little!