Hi Mildez,
WFC is the best - We had BFP on our first attempt through ICSI - who's now our 2yr old DD. They were really easy and simple to communicate with, fast in their response and I found the wait times not too bad. Since then, they've also had whole new facilities build which are supposedly 5* quality. DH and I decided on our DD 2nd b'day to go again using one of our frozen blasty's and rang from the list of Dr's they take referrals from...had a 2week wait to see her (our previous dr had retired), and i'm now waiting for AF to come to start the cycle.
I have had friends go to other clinics and not only walk away with a huge debt, but no son/daughter and not always a very great experience with their staff. WFC staff were lovely. During my ICSI cycle i arrived to collect med's on the wrong day when all the staff were in a mandatory meeting. I ended up emotional and in tears in the foyer. The NUM came out from the meeting, retrieved my file details, organised my meds (and a cool drink!), and sat with me till i regained composure - They were wonderful. I live an hour away from WFC and wouldn't dream of going anywhere else!

To answer your question though - to book in, just give them a ring. They'll walk you through it all from there!!
Wishing you all the luck with your chosen clinic and of course, your cycle when it starts!!