Firstly you need a good dedicated anal lube. One of our most highly recommended is Sliquid Sassy Glycerin-Free Anal Lubricant. It has 9 reviews and is 5 star rated!
Sassy is still a body friendly water-based lubricant but is slightly thicker, so makes anal play easy and comfortable. It's also exceptionally long lasting and water-soluble so you can just add a little water to it and it'll renew itself.
When it comes to anal sex toys, you may want to look at prostate massagers rather than just straight butt plugs or dildos. Although initially quite hard to stimulate, once you've experienced a prostate orgasm, you'll never look back!
The Aneros toys come in lots of different sizes and shapes and there are even dedicated forums on the internet that give lots of advice, recommendations and tales of personal experiences that you may find useful.
What you want is a bigger prostate toy (I know it goes against everything you think is right, but bigger is better in this case!) because the bigger the part that is supposed to stimulate the prostate, the easier it is to do it. Take a look at the Aneros Peridise Unisex Anal Toy Beginners Two Pack for example.
At the end of the day, you know what you want from an anal sex toy and what you want it to acheive so it's worth simply looking through all the categories and reading the reviews until you find something you like.