You need to know the number 42......
For the webcam may work but you will outgrow it very very quickly. Plus its not really sensitive enough
the 80 mm refractor is more than sufficient for the job so just look at either a qhy5, orion starshoot autoguider or a meade DSI 2 are the mid range ccd's of choice for guiding. the next step up is the starlight express Lode star and sbig 402-me
Brendan