There are a few tools, either online or offline, that could solve (find equilibrium) in a game explicitly given as a real-valued matrix.
Such tools are Game Theory Explorer and Gambit.
However, as far as I know, these can not be used for finding equilibrium in a game with parameters.
For example, consider a two player game symmetric game, parametrized by some $x\in[0,1]$, which is given by the following payoff matrix for the row player (and $A^t(x)$ for the column player): $$A(x)= \left( \begin{array}{ccc} \frac{x}{2} & x \\ 1-x & \frac{1-x}{2} \\ \end{array} \right) $$
Each equilibrium in this game can be represented as $<p_a,p_b>\in[0,1]^2$ where $p_a$ is the probability of the first player playing the first strategy and $p_b$ is the probability the second player plays the first strategy.
Analytically we can find all the equilibriums for this game
$$EQ(x)= \begin{cases} \{<1,1>\}&\mbox{if } x>\frac{2}{3}\\ \{<3x-1,3x-1>,<1,0>,<0,1>\}&\mbox{if } \frac{1}{3}\leq x\leq\frac{2}{3}\\ \{<0,0>\}& \mbox{else} \end{cases} $$
I'm looking for a solver which is able to understand inputs like $A(x)$ and produce $EQ(x)$.
Is there a tool which solves parametric games?