Answer: Many perennial gardens are created over time by trial and error, but a good way to learn is by visiting public gardens, nursery display gardens, and the gardens of friends and neighbors. Gardening friends can also be a great source of plants that grow well locally -- perennials need division from time to time and this process results in "free plants" to share.
You might get some great tips from gardening books in the Dummies series (lanscaping, general gardening, perennials, for instance) or since you are in New England, a book by New England gardener Elsa Bakalar called "A Garden of One's Own: Making and Keeping a Flower Garden" published by William Morrow in 1994. If your library doesn't have these, there are inexpensive used copies available from online bookstores such as Amazon.com.
Your local county cooperative extension in both states may have publications and possibly classes as well as Master Gardener programs where you could find free help with your planning and learn gardening skills. Learning to propagate your own plants from seed, cutting or division is fun and also a huge money saver.
The following site provides links to the state extension services.
I hope this gives you some ideas.
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