Look on the web for a data base that can be converted to an undirected graph. For example, in Science there is a data base of proteins and their interactions. Each protein can be represented by a vertex and two proteins that interact are connected with an edge.
Find a data set that will yield a graph with at least 1000 vertices and a number of edges that is roughly in the range or one to two times the number of vertices. Thus, the graph will be quite sparse and have many connected components. Find all connected components and create a table with the number of components of each size. For example, 312 isolated vertices. 124 components consisting of two vertices connected by an edge, 29 components with three vertices, etc.