Also, ask for court ordered counseling with you and the kids if it is really bad. This will get them in a room with you at least and a person who can steer the direction and get them talking without mom interrupting.
As far as finding a lawyer, go to family court and sit and watch in waiting room. Some courts are even open (by law as long as you are not going to testify you can be in the room too but many dont have chairs or set up to handle it). Watch and see who is good with other clients. You can also call a few lawyers and have a free or small fee first meeting and interview them. If you interview them, your ex can never use them, tactic some use.
DO you have a court date already? If not, you can file yourself too at family court for visitation only (Before you file for divorce as divorce may take years......). Family court will be cheaper and then you can take that order and merge it into the divorce later. This will get your ex out of the visitation conversation if there is a set schedule when to see them. Also email or text your ex once or twice a week asking "I miss the kids and they need both their parents in their life, when can you meet me to see them, maybe at the library or mcdonald for an hour? Let me know which day would be good." This gives you documentation to show you are trying with your ex. If the kids are old enough to have cell phones or social media...text them "dad love you, call anytime" " how was school, just checking on you, love dad". You can send them things in the mail, or drop off if ex allows....Valentines day package ? If ex answers meanly, ignore, screen shot it, save messages.
Good luck!