Hey there, Nick from Websolr here.
Of course I'm a bit biased here, but where search is concerned, Solr is a really great option for you. Certainly I don't need to rehash all its features and benefits here, when you could just as easily figure that out with a bit of light research :)
It's a very fair point that getting started with Solr has a bit of a learning curve to it. With Websolr we (fizx and I) think we at least have taken the hosting and configuration side of that off the table. But there are still client libraries to learn, and schemas to configure. I think learning some of those basics is a great investment that will pay off, but the up front cost is certainly there.
A word about crawling: it's definitely doable with Solr. The advanced approach is to use Nutch[1] to fetch and feed content to Solr. The simpler way is to use wget. In fact, I've got a basic shell script[2] to show off the latter :)
I'm always game to talk about how Solr can see more general usage, particularly when it comes to lowering the cost of getting started. So feel free to keep the questions/feedback/brainstorming coming.
1. http://nutch.apache.org/
2. https://gist.github.com/774946