I also bought many guides and WSOs on list building. Some of the methods taught were great; some required huge investments and some had pathetic results. But all in all, I think I've narrowed it down to 4 methods that I've found are what really works for me. I acknowledge that there are others out there who may disagree and had more success with other ways then good for them but this is what has worked for me.
So without further ado, here they are:
Every niche has a major forum that people in that niche go to. For IM its right here in Warrior and I've found that the best way to get subscribers for free is to provide great advice and give generously to the community.
Use the forum signature to link to your squeeze page and offer and go around answering questions related to your offer. Also, check to see if the forum provides any advertising avenues. And If you're building an IM list, this is even easier. You could post a WSO or buy a Banner Ad for a huge boost in traffic.
List Building Services
List building services are basically services that offer to add subscribers to your list using a variety of techniques ranging from co-registration to contextual advertising. I know some of you have had bad experiences with list building services, but to me I think it's a matter of weeding out the bad ones from the good. There are many people who have used these services and built a decent list with it. Some of the better services I recommend are getsubscribers, listopt and leadsleap.
An Ad Swap is basically a cross promotion between 2 marketers with lists who agree to promote each other's offers to their lists. Marketer A promotes Marketer B's offer to his list and in exchange, Marketer B promotes Marketer A's offer to his own list. The subscribers get free content and both marketers get to increase their list size. It's an all win situation!
This is my favourite way to build a list cost effectively as it requires virtually no cash. Simply find a marketer with a similar list size to yours and request for an ad swap. If you're in the IM niche, you can easily find these marketers here in the Warrior JV section.
Solo Ads are similar to Ad Swaps in a way where you're asking other marketers to promote your offer to their lists, but this time, you're paying cash instead of a cross promotion. I've found this to be the fastest and most effective way to build a list. The key is to find people with responsive lists. It takes a while but it's really worth it in the end. If you've got a huge budget then you'll definitely want to purchase solo ads. You can find solo ad offers here in Warrior or you can check out safe-swaps.com.
So there you go. There are other methods out there like PPC, article marketing and so on but some of these methods either cost too much or require huge amounts of time and effort. If you're just starting out in list building, I believe using the above 4 methods is more than enough to build your list from scratch without too much risk, cost or effort.