Great Resources
Normally, I am not very into writer’s guides. I’m not the type of writer who plans or outlines or pre-plots or any of that so their advice rarely helps or even appeals to me. But I have found over the years a few books that have helped me strengthen and improve my writing.
I’m not a spokeswoman or anything and I’m not telling you to run out and buy these books, they just happen to be ones I have found particularly useful.
Passionate Ink: A Guide to Writing Erotic Romance – Helped me understand how to make erotic romance erotic
On Writing – Every page is just filled wisdom
On Writing Romance – Showed me that the romance part was the most important part
Sex Tips For Girls – While not a writer’s guide, it is chock full of information. Totally 80’s and really fun
Lisa Fox Romance 
I have the first two myself and found them very helpful.
I’ll have to look into the last two, especially the last one. It does look fun! =)