Venusaur is Base set, holographic, non-first ed, non-shadowless, probably around $5
Raichu is Base set, holographic, non-first ed, non-shadowless, not much more than $1
Machamp is Base set, holographic, first ed, non-shadowless, nill. Available through the original starter box.
Dark Machamp is Rocket set, holographic, non-first ed, not much more than $1
Entei could be either the Promo reverse holographic, Revelations holographic, or Revelations non-holographic. Please describe
Ancient Mew is not sealed, probably around $1-2
I can't tell for Entei, Articuno, or Zapdos. I need a better description. Is there holofoil on them? If so, where? What set are they from?
www.pokemonlabs.com has a list of the set symbols.