LTS is an abbreviation for “Long Term Support”.
A new LTS version is released every 2 years. Starting with Ubuntu
12.04 LTS, both Desktop and Server versions will receive 5 years support. There is no extra fee for the LTS version; we make our very
best work available to everyone on the same free terms. Upgrades to
new versions of Ubuntu are and always will be free of charge.
Here, support means:
Updates for potential security problems and bugs (not new versions of
Availability of Commercial support contracts from Canonical (if applicable)
Support by Landscape, Canonical's enterprise oriented server
management tool set (if applicable)
So it is not a usual 'technical support' with a toll-free number and a technical support executive that you might be thinking.
If you want any help, you can always describe your problem here or in ubuntuforums and surely you will get help.
Read this to know how to ask a good question in Ask Ubuntu!