As this is my first build I am constantly struggling with my lack of skills. The car electrics have been a steep learning curve for me. When putting things like earth points in is there anyway I can test the connection to check to see if its conducting electricity as it should? I have a multimeter and I constantly test for continuity and so far I have got very low numbers. Surely everytime you put in a connection it creates extra resistance within the circuit? Then this resistance can be measured? How do I do this and what is a good result for a earth point? Or a butt connector?

Cheers

Set your meter to the ohms scale to measure resistance. If it is not an autoranging meter set it to a low resistance scale. Touch the 2 test leads together and you will probably get a reading of about 0.2 ohms.
When you test a new joint for resistance a 0.2 ohms reading means that you have a very good connection and 0.3 to 0.4 ohms should be alright.

Don't worry about your 'lack of skills', it's just that you don't know stuff yet.
You're absolutely right, every connection will add to the resistance, and as Mal says, anything in those ranges is fine. (actually, it's not easy to measure low resistance accurately, as the leads themselves have resistance, there are clever ways around this but not needed here).
All you're looking for is a really bad connection, which will show up.

[Edited on 26/2/12 by richmars]

All above is correct. The only thing I would add is to not look into this too much. If you want to check I would be happy with setting the multimeter to continuity check (audio beep) and use that.

HTH