you should learn to build at you rown. everything has its advantages and disadvantages. in building landing pages, sometime you will get very good resources of traffic and sometime not so good but ultimately the will give you benefit.
If you are using ppc or ppv the only reason i can see to build a landing page would be to build up your own email list for marketing - but i dont think they are the best idea - for media buys tho they may work better!
Direct linking is not permitted at a lot of places including by the big G. If you're building a landing page you have the opportunity of pre-selling to make the visitor click through to the offer and convert.
I usually split testing via cpvlab by rotate 50:50 LP and DL, which got good conversion i will use it.
When your ROI is good you have to scale it up
Do you reg a new domain and build a new site for each offer or do you have a single site on which you create a new page / section for each offer?
I am starting to toy with the idea of constructing a LP so I can use adwords, but I am just not sure of the best way forward; Create a new site for each offer (costly and time consuming) or just host all on the same site.
I have a domain coolgiftoffers.com which I might use to host different offers and then use that site for tending my campaigns to Google?