Google spreadsheet questions

[nancylebov]

I'm working on a spreadsheet for my mailing list. I've never really worked with a spreadsheet before, and certainly not with google spreadsheet. Once I've got all the names and addresses nicely pinned down in their little boxes, how do I make them into a comma-separated list?

How do I edit inside a cell? And what may be the same question, how do I copy what's in a cell?

Update: Small victory--I found out that I use the insert key to be able to edit inside cells. Inspiration struck after I used delete to clear a cell out.