Some suggestions
Katie Mitchell - the theatre director. Quite easy to catch one of her productions in London but it may be in German
Peter Brook - he has written a lot, you can see films of his productions and his ideas are always challenging.
Antonin Artaud - you feel like screaming, here's your chance!
Max Stafford-Clark - action that text
Jacques Lecoq - start with a mask end up with physical theatre
Robert Lepage - for the technically minded
Vsevolod Meyerhold - time for bio-mechanics
Jerzy Grotowski - Poor Theatre is not quite what it sounds like. This site will get you off to a good start.
Eugenio Barba - The Paper Canoe, what a great title
Augusto Boal - Forum theatre is not going to work for a Solo project but does he have other useful ideas?
Tim Etchells - is it theatre? Push the boundaries.
If you want to see a longer list with some helpful links.