I believe that the best method(s) are the last two. Method number 1 is messy and unprofessional:

"The best online resource on the Internet is Wealthy Affiliate. Please go to google.comto sign up"

Your reader is left facing a mess of code, and although it's highlighted as a link it's generally scruffy. So let's look at the last two in a little more detail:

"The best online resource on the Internet is Wealthy Affiliate. Please click herefor more information".

Comments have been made about older users needing to see an obvious link otherwise they'll get confused. I understand that, but I also understand that the sort of heavily coded link I'm using here is equally daunting, so masking it under the word "here" should offer an effective compromise, and I believe leaves little doubt about what action is expected, nor what destination will be reached if the trigger word is clicked.

The last option is my most commonly used method. It requires a less obvious and more inclusive form of writing. Rather than issuing an instruction (click here, click this, go here) it makes an assumption that the reader is on your wavelength and will comply with a more subtle approach. This isn't the place to demonstrate it fully, but your writing should draw the reader in to the point where an obvious link (Wealthy Affiliate University) is clicked because the reader knows that we're in this together and this is an action I recommend he takes:

"Without doubt, the best online resource available today is Wealthy Affiliate University. When you visit the site you'll be amazed at the sheer number of FREE servicesyou can use, and the community is helpful, and above all friendly"

You'll have noticed that I've used two links here. In this example they go to the same place, but in reality you may choose two destinations. It's up to you. Always be aware though, that an overuse of links will get your a*** kicked by Google.