What was your experience with SEM Management Tools (like Marin Software, Kenshoo, AdCore, Acquisio, etc)?

First of all, finding keywords that are relevant to your products or services is the first step in an SEO effort. If the words are not under high demand for advertisements, the keywords can be more cost effective as long as there is still sufficient search volume. In other words, you want to make sure they keywords are something people use. The next step is a solid content strategy to employ the keywords in a natural way. I find the SEO Table at search engine land to be the best guide. You can find it at http://searchengineland.com/seotable. The key is to use the good practices, such as incorporating words in your articles and posts as well as URLs, and capitalizing on external sources, such as Social Media. At the same time, you artificially loading up on keyboards.

We work with one of the big cruise sites in the UK and it's all about making the site deserve to rank higher by continually improving the site via design & content. Google wants to rank popular sites so you need to (as Simon points out) figure out ways of getting influential sites to talk about you and link to you. PR is the only real way to build links these days.

Here is how I'd suggest you learn SEM: #1 - Open a Google Adwords Account (You can search for free credit / promo codes) online and play around with it. #2 - Review all of Google's training material: https://support.google.com/adwords/?hl=en&page=examstudy.cs#topic=3119071 #3 - When you finish Google's training materials, then read about Adwords on the web. Here is one good resource and you can Google for more: http://www.wordstream.com/adwords-for-dummies #4 - Sign up for an affiliate network (e.g. Commission Junction or Linkshare) and use your free credit to promote another company's offer. #5 - Once you feel comfortable with Adwords, consider building out your own Lead Gen websites or selling leads to existing affiliate networks (e.g. Motive Interactive or Integrate.com) #6 - If you'd like to learn from someone else, find an entry-level job at an agency: http://www.indeed.com/q-PPC-entry-level-jobs.html #7 - Another good way to get good at PPC if you work in an in-house marketing role is to hire someone to audit or manage your own account for a period of time so you can learn how they think and what they do. #8 - One word of caution: Google takes a minute to learn and a lifetime to master. Their default settings make it very easy to waste a lot of money so really make sure you know what you are doing before you spend too much money.

Depending upon what aspect of AdWords you want to automate, you can look at various tools. As Megumi suggested, Marin is a good option for bid management. You can have a look at Optmyzr (optmyzr.com) to automate account management activities. Cyfe is another option to automate reporting and building dashboards.

Technically you can bid on competitors. Take for example Autotrader who bids for keywords such as Honda, Ford, etc. But the best advice is actually here http://searchengineland.com/the-complete-guide-to-bidding-on-competitor-brand-names-trademarked-terms-118576