It is possible to search for and find an Ancestry offer online, but as I have said before, the free option has its drawbacks. The reason I say this is because it is very easy to use Ancestry offers to sign up, as well as the fact that many of these sites are run by scammers who are looking to take your money. These sites will either be offering a product or trying to sell you something. In my opinion, the worst ones are the ones where they actually ask you for your personal information so that they can get things started.
When you are looking for an Ancestry offer that is free to join, I recommend using any of the major search engines. These search engines include such sites as Google, Yahoo, and MSN. The reason I recommend these sites is that they are very popular and therefore it should not be difficult for you to find a good selection of them. However, there are some sites that are better than others. For example, you may want to use a site like EzineArticles, because they are much more likely to be completely honest and provide unbiased information.
Once you find an Ancestry offer that suits your needs, you need to take a few minutes to apply for the free membership. This will usually take about 5 minutes or so, depending on how fast you read their signup page. After you have joined, you can start searching on the site. Just remember that you should only look at family names, not full names as there is too much chance of you finding someone with that type of name. I have found that when you search using just the first name and last name, you have a much higher success rate.