I usually only only fly GA aircraft in VFR conditions. When lodging a flight plan from an uncontrolled airport to a controlled airport, will I automactically be told by Centre to switch freq's and contact app/tower or am I expected to switch freq's myself when nearing the destinatiion? Many thanks in advance.

On a pure VFR flight, without radar advisory service, you are on your own.  Depending on the speed of your aircraft, you would contact tower 10+ NM out to get landing instructions.   

Dave

Tks Dave