Whew, great question.
Well since I'm experienced with ppc, I'd spend most of it on that. But I wouldn't suggest that for the newcomer to Internet marketing. All my answers would depend on some things...
1) How much I know about PPC
2) How popular is this related site that my ad will be placed on? If it's a notorious site in my niche then I would be more inclined to spend more of my money on an ad here but if it's a no-name site I would be leery of advertising on someone else's site.
Just for the record, I think directory submissions are becoming more and more worthless over time. It's all about backlinks from key sites and less about these directory sites. I believe the webmasters of these directory sites know how to boost their PR to make their site look important thus sucking money from unsuspecting webmasters who think a link there will boost their traffic.
Don't get me wrong, directories were key a few years ago but their value has lessoned tremendously if you ask me.
I'll add an item to your "Other" list. How 'bout spending money on a basic book about Internet marketing. Most people who want to make money online are simply not marketers. And if you don't know how to convert traffic, there's no point in spending money on PPC, ads, etc.
If you ask me, education is what's missing out here and it's worth taking the time to spend the extra dollars in a Ken Evoy or Corey Rudl book just to understand the 1-2-3's of Internet marketing.
There are so many e-books on Clickbank on "The Secrets of Getting Rich" or some related topic. Yeah, these authors are getting rich because they are marketers and they know how suck people in. They give away some of their Adwords, Adsense, etc. tactics but without telling you the whole story of how you need to learn to become a clever marketer FIRST before you spend money on advertising.
JMHO.
