[Ted S]

It is unlikely you'll get a 2% sign up from an email marketing campaign unless you pay for a promotion in a very, very targeted list. The fact is, email marketing, when properly done, is very, very expensive.

"Renting" lists where you get a big data file of addresses appears cheap but it's really just spam, or a step away from it, and the results are as bad as the method. You're list might get a 10 or 15% open rate but opening an email is only step one. Step two, they have to click... that's probably 3-5% and then step three, they have register. A good site might pull as much as a 7-8% sign up rate but wait... when you do the math look at what's left.... 300,000 * 4% = 12,000 clicks * 8% cvr = 960 sign ups.

And mind you, these would be fairly good results. A well developed email campaign, a decent list, subject and body copy that passes through spam filters, a strong offer to get the click and a solid landing page that can draw a sign up 2 times that of the typical "free offer". Doable but unlikely for a first time email marketer and non-optimized forum. What's more likely is that you get a list with a lot of dead addresses, encounter spam issues, aren't targeted enough and end up with a CTR of 1-2% which takes people to a decent landing page that pulls 3-4% conversion rates. So from 300,000 emails you get 100 - 250 sign ups. If your email list costs you just $500 that's $2.50 - $5 per user -- if your list cost $1000 well, then double those numbers. There are better ways to get members.

But wait, I'm not saying email is bad... email can be great! The trick is finding a good list and having enough budget to afford a reasonable client acquisition cost (CAC).
In this day what you generally find is placements within an existing newsletter or renting a send where the company's branding and layout is wrapped around your template. These programs cost much, much more but they also come with something that generic email lists don't -- user loyalty. It's better to spend $5,000 to get 75,000 opens than to spend $1,000 to get 7,500.

Having a strong offer and taking people the right page is also crucial. Forums aren't like e-commerce sites, you don't have a discount or free shipping your have to market to the right people and provide them one heck of a reason to get to your site. When they do get there it doesn't stop. Most forums just expect people to find their way to registering, that doesn't cut it. When you're paying for marketing, you need a customized landing page with the features & benefits of signing up, a very short sign up form and limited interruptions from other features.

Good luck!