There's the list, actually, it's not ordered (you will probably noticed the influence of some of you guys):
Vetiver (Thing Of The Past…)
Circulus (Clocks Are Like People…) - the debut is better
Espers (self-titled, II…)
Strawbs (Ghosts, Grave New World)
Gryphon (self-titled, Midnight Mushrumps, Red Queen To Gryphon Three)
Hoelderlin (Hoelderlin Traum)
Stone Angel (Early Morning Hush)
Mellow Candle (Swaddling Songs)
Campo Di Marte (self-titled)
Uriah Heep (Salisbury, Sea Of Light, Firefly, Sweet Freedom, Look At Yourself)
Devendra Banhart (Oh Me, Oh my)
Six Organs Of Admittance (School Of The Flower…)
Henry Cow (Western Culture, Unrest, Leg End, In Praise of Leaning) - All good choices
Spirogyra (Bells, Boots, and Shambles, St. Radigunds…)
Trader Horne (Morning Way)
Midwinter (The Waters Of Sweet Sorrow)
Magna Carta (Lord Of The Ages, Seasons…)
Steeleye Span (Parcel Of Rogues, Below The Salt, Now We Are Six, Commoner’s Crown…)
Les Rallizes Dénudés
Magma - (Magma (Kobaia), K.A. …) - Add Mekanik Destruktiw Kommandoh, Kohntarkosz and Udu Wudu to the list
Gong ( Leave It Open…) - I've never heard of this 
Mountain Ash Band
Gentle Giant (Free Hand, Three Friends, In A Glass House)
The Dirty Three (self titled, Horse Stories, Ocean Songs, Whatever You Love, You Are…)
VdGG (Pawnhearts, Godbluff…) - excellent! Also add H to He and The Least...
Premiata Forneria Marconi (Per Un Amico, Storia Di Un Minuto…)
Banco… (Io Sono Nato Liberio…)
Baleto Di Bronzo Ys
Locando Delle Fate (Realle Academia Di Musica…) - erm... Reale Accademia di Musica are a separate band, not an album by Locando della Fate
Quella Vecchia Locanda (It Tempo Della Gioia, self-titled…) - both very good
Il Rovescio Della Medaglia (Contaminazione) - one of my favourite Italian prog albums
Spirogyra
The Incredible Straing Band – The Hangman’s Beautiful Daughter
Silly Sisters (self titled) - my mother has this but I forget what it sounds like
Bert & John
FC (What We Did On Our Holiday, self-titled
The Albion Band
Simon Finn
Mahavishnu Orchestra (Bird Of Fire, Apocalypse, The Inner Mountain Fame…)
Iancu Dumitrescu - interesting choice... just be cautious!-
Homotopy To Marie – Nurse With Wound