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.
There is many ways that can help you automate bid management:
I'll not recommend an automatization tool.... Adwords Editor is very good to manage multiples campaigns and accounts.
Optmyzr, no question. It was built by the ex-adwords evangelist at Google and is all about productivity. DM me for more info, we use it day in and day out on my team.
I’ve been working with Acquisio for 3+ years and have been really impressed. Their BBM tech has had a significant impact on the performance of our campaigns, we generally see a 40% bump in performance when we take on a pre-existing account and layer on BBM.
I did look at the others but the cost/benefit ratio on Acquisio was strong for our scale (1M-2M annual).