1: Short answer... it depends which strand you want to work for... start with one, and the others will rapidyl become hostile towards you. The start point of each Strand mission has been identified in other posts to this board - try searching past messages - it works, honest!
2: An early source of low-risk funds is to fly a fuel-podded shuttle (or better, a scoutship) to Mira, and accept a mission to establish diplomatic relations between the Miranu and Humanity.
2a: Go to Pax station and buy crassworms. Take them to Omm and sell them there. Buy medical supplies (unless the Monks are on strike), and take these to the Ariane system. Sell medical gear, and buy equipment... take equipment to Pax. There are alternatives, but this is a pretty sexy little route. When you have a few thousand free credits, consider hiring freighters, and take them on the same route. Don't stop for anything or your 'escorts' will be blown out of the sky... just jump, jump, jump, dash for the spaceport.
3: Watch out for a message in the bottom left of the screen, like 'Okay, you retrieved the <whatever> from this ship.' For mission-related retrieval of goods, you don't get the usual boarding 'interface'.
That's it - good luck, captain.
------------------
"I wear a helmet
But I've got a bare chest
I do some talking
My phaser does the rest
Don't like your tentacles
Don't like your face
Don't like your planet
Think I'll lay it to waste
'Coz I'm Rambo in Space
Yeah, I'm Rambo in Space"