If you want to place the code in a specific spot on your WPMU pages, edit the template(s) you will be using, by modifying their code. You'll have to do it the old fashioned way: edit the source code, then FTP the changed file to your server.
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Warning!!!! Not autoblog related content ahead!!!
It's kind of strange, but everyone jumped on the autoblog bandwagon like a bunch of alcoholics on a bottle of MD 20/20.
For those of you looking for something different, I've mentioned Squidoo before, but I'm not sure anyone was paying attention. Squidoo.com allows you to create a "lens" about whatever you want. They handle the monetization, and you get a cut of it. There are a couple things about Squidoo that really rock:
- It's free! No domain to purchase, no hosting to worry about. Totally free.
- It is a well respected site, and as such gets new pages indexed very quickly and they usually rank well.
- Don't worry about where to put your ads, Squidoo does this all for you. Sure you have to split the profits with them, but you have absolutely ZERO overhead, so quit yer bitchin'.
- You control the content and modules on your page. Want to fill it up with more advertising? Add some Amazon modules. Want more content? Add another text module. It's up to you.
- Get 'Lens of the Day' and you could see a nice spike in traffic, both to your Lens and any of your sites linked from your lens.
- The links are NOT "No Follow" like a lot of blogs and Wiki-nazi-pedia.
- Create as many lenses as you like. There's no limit.
Need an example? Here's one I made in about 30 minutes to compliment my
Soulja Boy Dance blog:
Crank That Soulja Boy on Squidoo
Regardless of whether or not you're an auto-blogger now, check out Squidoo. If nothing else, it can help you SEO-wise.
/edit/ if you have a Squidoo account, do me a favor and give it 5 stars when you visit

I'll do the same for your lens