I recommend you not to do it.

Fiverr is good for lots of things, but not for buying backlinks.

www.majesticseo.com.

This is a very good free backlink tool. I highly recommend it.

I am currently using 247-host.com as my host. Here is my review:

Price: 9/10 (fair enough).
Customer support: 6/10 (they need serious improvement).
Uptime: 8/10 (my sites were down for some at times).

Overall, I think they are an alright host with rooms for improvement.

If you are looking to buy domain names for cheap, buy from Godaddy. They offer lots of coupon codes.

Which domain registrar is the best?

I think Namecheap and Godaddy are the best.