As an SEO consultant, I've done my share of experimentation with different SEO tools. My job is to try new techniques, figure out what doesn't work and what does, and spend my time doing the latter.

As a result, I have a lot of people asking me about my favorite SEO tools. The followings SEO tools are in my opinion the best SEO tools you can buy, when used correctly. Like all tools, some of them can be abused, but if you build your SEO campaign ethically and meticulously, you will succeed using these tools.

So here goes:

1. 1 Way Links - This is by far the best blog network out there. I am a member of two other blog networks built by bigger names in SEO, but this one far outshines them on the number of links I can get for my clients and the ability to track where they're coming from so I can build second tier backlinks when necessary. Note that it does require some technical knowledge in order to join the network - you must contribute a blog of your own to the system and set it up properly. You may contribute multiple blogs and get more posting credits, but they must be on unique Class C IP addresses.
   
   
2. 3 Way Links - This is a great "set it and forget it" tool that works best on lower competition keywords, but it definitely gets you part of the way there in your SEO goals, even if you are chasing high-competition keywords. It is is also great for building PageRank over time.
   
   
3. The Best Spinner - This is an absolutely essential tool. Don't waste your time on other spinning software. This one rocks. It's very easy to use. Spinning is always a pain, but this tool makes it as painless as possible.
   
   
4. SE Nuke - This may be a controversial pick, but it is a tool that can be used correctly or incorrectly. You can do complex SEO campaigns, including social bookmarking, article submission, Web 2.0 profile creation, etc. If you purchase this one, don't just dive in and use it before you go through the training modules and doing some testing on non-critical websites. That's because you can easily descend from whitehat to grayhat to blackhat SEO using SE Nuke without even knowing it with just a few clicks of your mouse. It's extremely powerful, but take the time to understand it before you jump into it. I recommend the lifetime license so you don't just give up after a month or two. Stick with it, it's worth it.
   
   
5. Aweber - This is a cheap but reliable autoresponder system. Infusionsoft is better, but if budget is an issue, go with Aweber.
   
   
6. Infusionsoft - This isn't an SEO tool, per se, but it is an essential drip marketing tool that is more like a CRM than a simple email list manager or autoresponder. The amount of granularity you can achieve in understanding and marketing to your prospects is phenomenal. Pricey, but definitely worth every penny if you have a moderate sized list.
   
   
7. Market Samurai - This is an essential tool for doing keyword research to determine the best domains to purchase or keywords to optimize for. At only $99, you can't beat the market intelligence you will gain from using this SEO tool.
   
   
8. Rank Tracker - This is an excellent SEO tool for checking your rankings on numerous keywords. Do keyword research, export your ranking results into nice looking reports customized with your business logo, and more.
   
   
9. Pay Per Click Loophole - If you want to build incredibly powerful PPC campaigns, this is the tool for you. It is a powerful niche PPC ad builder and PPC management tool that will efficiently power through major campaigns of hundreds of keywords and landing pages with ease.