Probably best to write your own extension method to do it.
public static class Extensions{ static readonly Random random = new Random(); public static IEnumerable<T> Shuffle<T>(this IEnumerable<T> items) { return Shuffle(items, random); } public static IEnumerable<T> Shuffle<T>(this IEnumerable<T> items, Random random) { // Un-optimized algorithm taken from // http://en.wikipedia.org/wiki/Knuth_shuffle#The_modern_algorithm List<T> list = new List<T>(items); for (int i = list.Count - 1; i >= 1; i--) { int j = random.Next(0, i); T temp = list[i]; list[i] = list[j]; list[j] = temp; } return list; }}