Hi, E.! Our 3 3/4 year old needs to snuggle at most bedtimes too. All our sleep "problems" started when we put him in a big boy bed a year ago. He was a great sleeper until then, and shortly thereafter, the yo-yo phenomenon began--up and down, all night long. I was at my wit's end, and a girlfriend recommended the book, "Sleepless in America: Getting Your Family the Sleep It Deserves," by Mary Sheedy Kurchinka. It was an invaluable tool for helping us cope with his change in sleep patterns.
A couple of questions for you: how much tv does he get in a day, or computer games? We found if our son got more than 1 1/2 hours, he slept less peacefully. Also, if we let him watch tv before bed, he has a really hard time going down. Ideally, I like the tv off 2 hours prior to bed; it helps him calm down.
Our son's bedtime routine is a little involved, and we only have one son, so we can spend this extra time with him: I read him 3 books, we brush teeth and go potty and put on jammies, then go to his bedroom and read a child's bible story, have prayers, and then turn on his music ("Velveteen Rabbit" with Meryl Streep and George Winston--it is the same every night. :) ), and then we lay with him for about 10 minutes. Our bedtime takes about 45 minutes total--it is a long time, compared to most of our friends. And lately, he still comes out and says he is lonely, or wants to give more hugs and kisses, or he has to go potty.
But what I learned about little ones and sleep is that they do not have the sleep skills that we do as adults, and it is harder for them to get themselves to sleep. Sometimes in their lives they will need more assistance in calming down enough before bedtimes and getting to sleep. This time in their lives is such a short time (although when you are exhausted it seems an eternity!), and soon they will not want or need us to be so involved in their bedtime routine. When our son is especially needy, I try to tell myself he will be grown up before we know it, and 10 years down the line, I will miss these extra cuddles. Doesn't always help, but sometimes it does. :)
I really recommend Kurcinka's book, E.. She has LOTS of really practical suggestions on how to coordinate your kids' routines to start to have more peaceful bedtimes. Also, REALLY try to limit tv/computer/loud toys, etc, before bedtime. It makes a load of difference to kids' ability to calm down and be ready for bed.
I hope this helps a little; I can only imagine how tired you must be! But this is probably only for a season--enjoy the extra cuddles, and use it as a little bit of downtime for yourself in the evenings. :)
God bless!