Looking to sell books from my website, how did you do it?

WordPress isn't a storefront. It won't let you take orders, but it is a platform that allows for storefront plugins as long as it's a self-hosted site rather than a free blog set up through wordpress.com. I'm not familiar with any of those plugins.

I've seen lots of authors just use Paypal buttons. And Gumroad is a fairly popular simple storefront used by a number of authors.

Excuse me if you've already looked into this and rejected it, but I don't think books sold from someone's site often do very well. One of my sites gets a good number of visitors too but only a tiny percentage of them will buy a book.

Amazon more than earns its cut of the proceeds imo from the giant amount of traffic it gets. And visitors to your site can always click on the book on your site and be taken instantly to its Amazon sales page.

Unless you have a conscientious objection to Amazon, I'd format the e-book on Kindle and the paperback on Createspace (easiest to use with Amazon because they're linked or maybe Amazon owns Createspace now or whatever), and sell them on Amazon. G'luck!

ETA: Also, unless all of your future books are going to be about the Fairfield Hospital Shooting, you might want to broaden the title of your website.

Before launching into doing you own sales I would suggest looking into your obligation for example with tax (VAT for UK sales etc), handling payments information, and dealing with disputes. There is quite a lot to retailing online that I would hesitate to jump into.

If you are still game it becomes a question of what to go largely manual with the fillable form to save money, or get a proper store plugin or service.

AP, all the previous suggestions are good ones. I can't complain about Amazon, as they do their part to help me sell books. I do a lot of promotion also. I have several publishers, but only one does any active promoting to sell my books, so if it wasn't for Amazon, and what I do, my books would just sit there. Selling your books on your own may have some benefit, but I really believe you would do better on Kindle or CreateSpace. I use a printer in California for limited edition paperbacks I use as promotional products. They produce a nice product for a fairly reasonable price, and I can send copies to reviewers when necessary - though I prefer sending PDF copies when they will take them. You want reviews, as they help sell books. So find good reviewers who will post reviews on a Blog, Good Reads, or wherever potential readers/buyers might see your book. You need more than just your Blog to promote. You really need a community, and Amazon reaches a lot of people. There are FB Sites that let you promote your books free. I have several listed on my FB Page, and post on them daily. I can't say they have been a big help in sales, but other writers have come to know me and my books through them. It doesn't hurt to be known.

Gumroad or Payhip are my personal favs for easy ebook purchase implementation, and both handle the strict EU VATMOSS regulations that veinglory mentions, which is fantastic for EU writers and saves effort on their end (Gumroad source | Payhip source). Both also support Pay What You Want which is a nice feature you can't get from ebook retailers (though Smashwords can be wrangled to give free downloads), and both mean you can supply multiple formats of your work (eg PDFs) for readers that prefer that.

Gumroad has a nice feature for releasing file updates, which is important to me. I think this is Payhip's version of the feature? It doesn't seem as user-friendly, going by the screenshot alone, but it'll still do the job. Payhip takes a 5% transaction fee after PayPal fees, Gumroad takes 3.5% + 30¢ per charge, I can't puzzle out which one would be cheaper for a $3-to-$5 ebook.

The percentage of readers who buy direct is always going to low, but you get a higher cut when selling direct, and you have a secondary point of sale if Amazon or other ebook retailers decide to do something evil. Also, it's nice to do something to give readers choice and flexibility.

I would love to see a comparison of Payhip vs Gumroad if anyone's tried both, as from what I've seen they both seem like solid services with strong features. I can't figure out which one has the lower fees though.