IMO, trading services can be a nice alternative if you can do something your contractors can't, and need. Think creatively too. Perhaps your company can't offer something, but maybe you or members of your team can - such as a website redesign, a new logo, a handful of guest blog articles, SEO help, backlinks, etc. Look at the skills your team possesses and see if one of those is tradable.
I've found that offering equity isn't as desirable these days. But if you do find contractors who are willing to accept equity, make sure you consult someone familiar with equity issues. The amount you give them may inadvertently force a valuation on your company that you may not want.
You could also try to negotiate a financing plan where you pay the contractors in the future with interest accrued. I'm doubtful that will work, but if you want to explore this option, you may have to draw up some kind of legally-binding contract for this. I'm no expert in this field, so you'll have to consult your attorney or accountant.
A colleague of mine was able to find passionate users to help him in development, design, and blog articles. However, he had a portion of his product already released and a niche community that is extremely passionate. It helped that he's also a notable member of that community and has lots of charisma ;)
One last idea. You could approach college students looking for internships. They'll be inexperienced and you'll have to work hard to find good candidates. But I've known startups who've been lucky enough to find wonderful interns who worked for academic credit. Now that they're profitable, they're hiring these interns.
Sure. You can pay with cash, barter, shares (equity), or donkey poop. It all depends on whether you have someone who is willing to accept it.
So most startups don't make it and 5% or whatever of nothing is nothing most freelancers aren't going to have interest in that perspective. Hey if you have a friend and a relationship with someone it's a different story but even then its about the relationship not the value.
I'd suggest you look at the freelancer payment from a different perspective. There is the crowdsourcing, to auctionsites to craigslist. Your not likely to get the same level of service and you'll need to have a strong communication model to engage the freelancer (email, web postings, very specific requirements and good turn around plus up front costs of escrow account.) This can help keep the price lower but you still have a cash outflow.
Another way to go is build what it is you are going to build. Get all that you can without the freelancer that way there is something that shows your serious when you try to barter or offer a portion of the revenue or get some type of defered billing. Perhaps you can even create an offer of something less then what you first envisioned without the freelancer that gets you started. This is really what scalling is about.
So just wanted to put some other ideas out there and why the base idea you have would be scoffed at by most freelancers. Good luck.