Hi Suzy,
Great to hear you have a calling.
A typical profile of the variable star observers I get to interact with is that
for many of them, that is the only type of observing they ever do and
they are entirely dedicated to it.
If you belong to one of the club's there in S.E. Qld, almost certainly they will
have a member who acts as a "variable star section leader" for the club.
For example, down here in Sydney, one of the ASNSW's hardest working
members is a gentleman named Adrian Saw. Adrian was awarded Life Membership
of ASNSW in 1995 and is also the club's variable star section leader.
See
http://www.asnsw.com/sections/variable.asp
When you talk to someone like Adrian, it is not uncommon to hear they
just stick to observations of, say, the same one hundred variable stars.
These become known to them as "their variables". As has been commented
about previously, the AAVSO is the variable star observing peak body and
so dedicated observers tend to file their reports to them.
Some observers in this region also report to RASNZ in New Zealand.
See
http://www.rasnz.org.nz/Sections.htm
They have been instrumental in southern variable star observing since 1927
and have a dedicated research group called "Variable Stars South".
See
http://www.varstars.org/
As far as useful contributions to the science of astronomy, then what what you
have read thus far with regard variable star observations is correct. If you want to
get some of your motivational energies really flowing, I hope at some point
you have the opportunity of attending one of the talks either by professional
astronomers or amateur observers or both where the science presented is
a direct result of variable star observations of which amateurs made a significant
contribution. For example, I remember talks by people such as Dr. Surjit
Wadhwa, a ASNSW member, a few years back at Macquarie University that
were exciting to listen to.
Undoubtedly there will be IIS members who are dedicated variable star observers
who can offer further advice and suggestions. Good luck.