I would like to know how these websites operate, lowermybills. com ,
lendingtree. com and similar ones to those.

Basically what I would like to learn is, how they make their money. Do
they contact all the lenders etc. they work with beforehand and make
some contracts and then they get paid as they send leads, or is there
a middleman like linkshare, commisionjunction etc. and they dont have
to face and contact the lenders themselves but a middleman provides
the service for these companies.

If my question needs clarification please ask, I will try to explain better.
If I need to put in simple words, what are you supposed to go through
to set up a similar service?

Hi,
Have you read the sites' Terms of Use?  Here they are, and one more: 

http://www.lendingtree.com/stmrc/termsofuse.asp?inline=true&source=23972&siteid=&esourceid=23972
http://www.lowermybills.com/misc/termsofuse/index.jsp
http://www.theloanpage.com/terms-of-service.aspx

They will give you some idea how they earn their money  - you agree
among much else to their releasing non-public info about you.
If the terms seem virtually the same, this does not have to mean they
are all in cahoots with each other.  It's legal text, a contract, and
like house and car rental contracts, the tried and tested wording
becomes standard.

On one similar site, I found a schedule of the fees that lenders pay
for receiving leads. The site said that your info would normally be
passed on to 3 potential lenders, which keeps them on the toes.  There
was a price per such lead of (?) $ 20, and a higher price for an
exclusive lead (only to that lender, no doubt under a special
agreement that he would pay for such when the lead's data fit certain
parameters, maybe location, amount ...).  and then there were
additional fees of $3 or $5 per lead for other factors, one of which
was when the lead had NOT checked his own estimate of his
creditworthiness as "excellent."
As an old-fashioned banker, that struck me as strange, but lenders in
this business are more interested in borrowers who will have to pay a
higher interest rate and may be under pressure to refinance, so such
leads are worth more.
And there were additions for mortgages in some states.

I hope this information can be of help.