In the first instance you have to write a letter stating your reasons for complaint to the Partner in Charge at the solicitors practice. Only then if you get no satisfaction can you approach the Law Society who are the regulatory body for solicitors.
Without prejudice, are you sure that it is definitely your solicitor that's holding up proceedings, and not the opposition or a factor beyond his control? I'm not assuming either way and there's obviously facts I don't know, but have you asked exactly what's holding him up?
The Legal Complaints Service is simply the ghastly old Solicitors Complaints Bureau in disguise. The same old dreary useless johnies are still there in the same rooms in the same building at the same address behaving in the same useless way. At any one time they have a minimum backlog of 18,000 unresolved complaints. A total waste of time.
I'm with Mustafa on this one. Complete and utter waste of time. Their offices were (and probably still are) in Leamington Spa - 4 years after they were flooded they were still using it as an excuse!!!! I would suggest a strongly worded letter to the Complaints Partner asking him to invoke his Rule 15 Complaints Procedure (of the Solicitors Conduct Rules) should get a response. Failing that, threaten to remove your business to another firm.
Unfortunatly this is what soilicitors do, its how they earn their ill gotten gains {our money} The longer the case the more money they earn. give it up as a bad job and move firms to one thats been recommended to you. Almost any solicitor will lie, stall and drag any case out for as long as possible. You know the old saying "how do you know when a solicitor is lying................You can see his lips move". Best of luck