Which genealogy site do you recommend?

Paying for some of these sites can be very expensive for stuff that is available elsewhere for less.

The facts that you need to research for a family tree are stored all over the place, on local FH sites. If possible, you should go to the primary source, where you see exactly what was recorded about the event.

The bigger genealogy websites have gathered together links to these primary sources, and indexes etc. They also have links to other people's family trees - treat those with caution. They have not all been thoroughly researched. They are pointers to someone else's opinions, but do your own checking.

You may find some more threads on this. Maybe start with one month on Ancestry (you can find a lot in that time). They do have help phone lines. You can build a tree on their website, but I built my tree on my computer with a program (there's a recent thread on that).
Why not go along to meetings of your local Family History Society, where you'll find really helpful people. This is especially useful if your ancestors are local.

Here's a recent thread about family tree programs
Family Tree Programs

Another thread asking where to start:
Where Do I Start

I found Ancestry to be the best overall site for English relatives. My daughter bought me a book about tracing your family on the net. There are loads of free websites including free bmd and freecen (births, marriages and deaths, free census). Just a word of warning. Try not to copy tree details wholesale as they may not be correct. I know I have at least 2 errors on my tree.
A free website where you can get help and advice is Family Tree Forum. Here people with loads of experience will help out in looking for details and make helpful suggestions. I found this invaluable, especially at the beginning.
As others suggest there is loads of free stuff around. The IGI has been a little problematic as not all the details are linked to the correct family.
Good luck with your research. It’s a never ending detective story and rather addictive. I use Family Tree Maker to input the information. If you need any help please pm me and I’ll do what I can to help.
Good luck

I use mainly the free sites now, when I do need to find anything else I use Ancestry. They used to give a free trial, 2 weeks I think, so you could do the basic searches - just remember to cancel the subscription if you don't want to pay to carry on. You can just have a month at a time whenever you want. Also note that anything you want a copy of download to your computer to print it, if you don't have membership running you cannot access saved records.

FreeREG, FreeCEN, FreeBMD all good. FamilySearch is another good one to look at, you can pay for that too.
County records also handy, most areas have parish records you can look at - online parish clerks.

Do note Ancestry rubbish for Scottish records I do not know about Wales or Ireland .

I mainly use Ancestry, but I supplement the information by using free sites or going to parish records when they are available. Scotland's People is good for anything north of the border.

I have been absorbed by genealogy for over forty-five years. When I first indulged, I received some excellent advice from an elderly long-term member of the “Genealogist Society”. His first point, I follow without fail “if you cannot prove it, you cannot claim it”; the next “skeletons in the cupboard everyone has and needs to be accepted before you begin”. I subscribe to Ancestry as an aid to tracing original source evidence which remains the guiding principle. Would I take any thing on Ancestry Public Trees as substantiation certainly not, too many are without research merit and incorrect with finds simply made to fit?