Sorry, I can't help much re: multiple languages and how you should be tracking. I would probably track each subfolder as a separate campaign, but I'm going to defer to someone else's opinion on this question, since I don't deal with multi-language sites.

Google Webmaster Blog posted this recently: http://googlewebmastercentral.blogspot.com/2011/12/new-markup-for-multilingual-content.html

They don't explicitly say that doing this will result in 'geo-targeting,' but if a site is presented as the "version for users in Mexico, in Spanish", you can bet that Google will likely be showing that content to Google.com.mx searches.

I absolutely agree as far as Google Adwords certification and recommend reading this post for more information on those:

• How to Become a Google Authorized Adwords, Analytics or Website Optimiser Consultant by Tom Critchlow

I don't tend to think of the Google certifications as SEO, strictly speaking, but for overall inbound / online marketing, they're absolutely respected, at least among other practitioners.

InboundMarketing.com is the closest thing to SEO certification that I have seen that I consider respectable. The courses they post are created by a number of well-respected authorities. Their FAQ says all courses are free, I assume that includes the exam as well.

Do you already have a job where you can practice SEO? Alternatively, do you have a personal website you can practice on? That experience is far more valuable then a certification. I don't think it lends much credence to any SEO agencies that are hiring, they're looking for things like hustle & creative thinking.

Between reading every SEOMoz blog post ever written (or at least most of the ones written in the last 2-3 years), as well as the Beginners Guide to SEO, and actually doing it on a site, you'll learn most of what you need to know.

Just my 2 cents, I've never heard of SEOCertification.org but for all I know they might be reputable to someone...

OK, to answer the primary question of "My questions is, how important is it that the newly-formed keyword/phrase also be evaluated for search volume?"

It's important to check on that keyword phrase, but in the case you presented, it's not going to be a huge factor in your decision process. Had the modifier shown 1000 searches per month, than it would naturally be more worthwhile.

It's very difficult to estimate long-trail traffic based on keyword data from Google's Keyword Tool. There are plenty of keywords that are listed as zero or negligible traffic, that send me plenty of visits.

You'll have to make the call for yourself as to where to draw the line in terms of what keywords to focus on for page-level, and what keywords to focus on solely within the content level.

In other words, some keywords will be valuable enough to dedicate a page to, meaning targeting that phrase in your title, h1, and in your content and images. Other keywords are just long-tail phrases that should be within the content but not have an entire dedicated page.

In the particular case that you presented, I believe that creating an article titled "10 tips for job interviews" would be an excellent way to rank for "tips for job interviews". Google is advanced enough to know that a piece of content titled "10 tips for job interviews" is equally valuable to a piece of content titled "tips for job interviews."

In my opinion, what you should really worry about is how you're going to get enough links to that piece of content for it to ever rank, not whether or not the person is searching with small modifiers like 10 tips, etc. I'd probably try and get 10 experts to each weigh in with one tip - this will be a much more valuable piece of content than something you write yourself. Otherwise it will just blend in with the crowd.