Hi Vijay

Firstly it depends on what type of WAN connectivity you already have. If you are using MPLS connectivity you can talk to your SP about running VPLS between your sites which allows you have the same vlans shared between your sites.

If your WAN connectivity is ethernet based then you can simply set the connections up as layer 2 trunks.

Another option would possibly be L2TPv3 which would allow you to extend a vlan(s) across a L3 routed network - see attached link

http://www.cisco.com/en/US/netsol/ns588/networking_solutions_white_paper09186a008017fa6e.shtml

Alternatively do you actually need to extend these vlans or do you just need to give access to the 5 vlans from your remote sites. If so you could just route between your remote sites and the HQ.

Jon