I have used Home Gain's zip code feed to my website with much success -- I pay $1.99 per click through for a particular zip code.  I 'own" a certain percentage of the zip code during a certain part of the day.  They rotate the time of day among the people who share the day, so that for example, if there are three agents who each have 8 hours of the day and if you got the worst 8 hours on Monday you'll get the best 8 hours on Tuesday, the next best on Wednesday, and back to the worst 8 on Thursday.  However, it doesn't seem like it is actually in 8 hour chunks like that -- I think it is done more in 2 hour time slots from what I can tell from my web traffic.  You set up your url to go directly to a "use the MLS for free" registration page and then the people have to register to get past that to get to your MLS.   I have it set so they can enter x@x.com if they like, with a little funny blurb that says that I will protect their privacy and if they will trust me, they will get lots of good info from me if they give me the real deal. A surprising number of people give me valid info, and I then set them up for drip email, newsletters, etc.  If they will give me a phone number, I try to call them as well, though most people will not give a phone number this early in the process.   

I have been so happy with the HomeGain pay per click that I have increased my initial order of clicks by about fivefold from my initial order and have a standing order for more capacity in my selected zip codes if one of the other agents cancels any of their time.

I have used this service to improve the "hits" to my webpage also and my natural placement on Google and Yahoo is greatly improved by it -- kind of like using stealth pay per click advertising. 

This may seem really steep to some of you, but this is in areas where the average home price is over $1 Million, so a single  home sale can easily pay for the whole year's "clicks" and then some.

However, I do NOT recommend their "Source 4 Sellers" service -- I have tried it a couple of times in various zip codes to see if one zip was better than another and it tends to mostly get people interested in re-fi's -- great if you do mortgage loans also, but not so good if you just want real sellers.  Everyone I've tried to call was not interested in actually selling or really in even refi'ing but just was curious about their property value and was wasting my time -- they don't do enough screening.  In my area (Los Angeles county beach cites) the pricey zip codes for this were $199 per month and the cheap ones were $110 per month. 

Hope this is helpful!

Best Regards,