Okie, did my first two trading runs, and comparing prices (in a spreadsheet I've made), I've come to the following tips for initial trading for now.
Azeban City - Beagle 2 Landing (Asellus System) routeAzeban: Buy
Fruit & Vegs (profit ~120 per item), then
Coffee/Tea/Animal Meat (all around ~310-320 profit) as you can afford them.
Beagle 2: Buy
Animal Monitors (profit ~120 per item), change to
Terrain Enrichment System or
Consumer Tech (profit ~430 each, I'm unsure if
Personal Weapons is an illegal item, if not change to that, it is ~600 profit)
Of course, once the demand for an item has been met, things have to be reevaluated.
I haven't checked what the other nearby systems gives you in profit margins - but this is a pretty safe run and will let you easily build up some starting capital to either upgrade your ship, or buy a new one.
Øystein