Step 1) Go to ezinearticles.com, or Google.com, or some other site that will let you find articles that you can republish (PLR is ideal).
Step 2) Take the time to read through these articles and find some that are high quality and provide value. This is very important. Quality is a critical part of creating any product.
TIP: Use the titles of the articles on EZA as a basis for your table of contents and your sales letter bullet points. They are designed to attract visitors after all.
IMPORTANT: If credit is required as a part of republishing the article, make sure you follow the rules. It doesn't cost you anything to give credit to the author of each individual article. Heck, if the author is famous in your niche, you could use that as a selling point in your sales letter. Just make sure you give credit where it's due, and that you do it in a manner that complies with the author's ToS.
Step 3) Now for the easy part. Open up a text editor (I recommend OpenOffice.org - The Free and Open Productivity Suite), and simply copy and paste each article in the order you want it to go. You don't need to worry about the footer of your ebook, as adobe reader takes care of things like page count and what page you're on. Once you do that, you can take the article titles and copy and paste them into your table of contents (for information on how to make a clickable ToC, please go here: How To Make Your Table of Contents Linked In OpenOffice Writer: Solution #2 :EZ Ebook Templates).
Next, come up with a snappy title for your guide (use the titles of the articles for inspiration), get an ecover made, put your name on, and bam! You're all done. A note though; instead of using "By: Your Name", use "Compiled By: Your Name". It's just more honest than leading your readers to believe you wrote the whole thing, unless of course you have PLR for all of the articles.
TIP: Use eBook Cover Creator - eCover Design Online Free to easily create ecovers online. Some of the templates are free! As for the others, it is both cheaper and faster than outsourcing.
True, the researching bit may take rather longer than 15 minutes, but the creation part won't take so long. Once you start making ebooks, and practice some, you may be able to go from scratch to finished product in 15 minutes.