Andrea,
VPLS I am afraid would not have any focused training course, or book. Since its more of a feature which works in amalgamation of Metro and MPLS.
So having said that, you may want to take Metro-E V3.0 Training from any Cisco Learning Partner.
Books wise again no focused book, but I am very sure you as well as others who may be intrested would find Metro-EThernet-Forum and VPLS.org Very helpful, and then ofcourse Cisco website is there to fill the GAP between the standards level language of MEF and using it practically on cli with help of Cisco website.
And last but not the least, it important to keep updated on these drafts as well.
L2 VPN Framework:
http://www3.ietf.org/internet-drafts/draft-ietf-l2vpn-l2-framework-05.txt
VPLS Using BGP Signaling:
http://www.ietf.org/internet-drafts/draft-ietf-l2vpn-vpls-bgp-06.txt
IP Multicast in VPLS:
http://www3.ietf.org/internet-drafts/draft-ietf-l2vpn-vpls-mcast-reqts-01.txt
VPLS Using LDP Signaling:
http://www3.ietf.org/internet-drafts/draft-ietf-l2vpn-vpls-ldp-08.txt
Provider Provisioned Virtual Private Network (VPN) Terminology
http://www.rfc-editor.org/rfc/rfc4026.txt
Happy Learning!!
HTH-Cheers,
Swaroop
PS: Stephen Morris has a book on VPLS, if you find it a little difficult to get a hang of the draft and MEF. the book is titled
"MPLS and Ethernet: Seven Things You Need To Know"
