When two or more people own land together, you are generally Tenants in Common - a legal term to mean each owning party has equal right to possession, use an enjoyment of the whole even though you own a percentage of the equity. You will need to file a suit to partition. A suit to partition is a lawsuit in which one or more owners sue the remaining owners (usually everyone falls into one of two alliances in these cases) and the remedy being sought is to cut up the ownership - generally this is accomplished by awarding each party sole ownership of a portion of the land representing each party's equity share.
There are exceptions to the general rule those occurring in cases where the land cannot be divided equally and in that instance, the court "may" order a judicial sale. Absent this very rare remedy, you cannot force the party holding out to sell his/her share, but you can divide the property into separate shares and each of you can sell what you have, though the buyer may not want the property unless they get it all so keep in mind, partition may give you an equal share but the share may be worth less than the percentage if the property is kept together.
Roy L. Reeves - Reeves Law Firm, P.C.
www.planoattorney.net