Need information on traveling to Montezuma, CR and Panama

I am traveling to Montezuma, CR this coming April. I would need to fly out of Halifax, Nova Scotia. What is the best airport to land in CR and what are the ground transportation options to Montezuma.

Well, one major airport in the country is San José (Juan Santamaría) airport (SJO) located near the capital. In most cases, that is the "best airport to land" in Costa Rica, since it is centrally located. There is another international airport in Liberia (LIR).

Once you're in Costa Rica, there are a handful of local airstrips, serviced by puddle-hoppers from Sansa and Nature Air. One of the airstrips is in Tambor on the Nicoya Peninsula, near Montezuma (a short taxi ride away). You could take a half-hour flight from San José to Tambor, or from Liberia to Tambor: according to Wikitravel, Nature Air and Sansa have daily flights.

Anyway, here's how to get from San José to Montezuma overland via Puntarenas:

1. Take the bus from San José to Puntarenas (about 2½ hours). There are buses hourly or every 40 mins, from 6am to 7pm, and it costs a couple of US$. They leave from corner of Av 12 & Calle 16 (Terminal Empresarios Unidos). Wikitravel says: "The trip will take a couple hours depending on traffic and weather conditions, but it's inexpensive." I think you can also catch these buses directly from Alajuela, the town where the airport is, west of central San José.
2. Take the ferry from Puntarenas to Paquera on the Nicoya Peninsula (about 1 hour). There are 2 ferry companies: Naviera Tambor and Ferry Peninsular (aka La Paquereña); both depart from Avenida 3, Calle 33 in Puntarenas. Each runs several ferries a day, and it costs less than $2. Ferry Peninsular has 6 daily departures from 5 am until 8:30 pm. Alternatively, take a lancha (water taxi), departing at 8 am, 1 pm and 4:45 pm, and also very cheap.
3. From Paquera, take a bus to Montezuma (via Cóbano) (1½-2 hours). My 2007 guidebook says: "most travelers take the bus from the ferry terminal directly to Montezuma ($2.30, two hours)". There are about 7 buses daily, between 6 am and 6 pm.

Edit: looks like you can simply take a direct bus from San José to Montezuma. My Lonely Planet (2007) says it's $10 and 9½ hours, but I suspect it's now faster due to the new highway "del Sol". See the information at playamontezuma.net:

The direct bus leaves twice a day (early morning and early afternoon) from the Coca Cola bus station in San José. It is called "Transportes Rodriguez". The bus goes directly onto the ferry in Puntarenas (so you don't have to move your luggage) and stops in Cobano, Montezuma, Mal Pais and Santa Teresa. From Montezuma leaves at 6.30am and 2.30pm. From San José at 6am and 2pm.

Alternatively, via Jacó:

1. Take a bus to Jacó. There are frequent buses from San José's "Coca Cola" station; it takes 3 hours and costs around $5.
2. Take a jet boat from Jacó to Montezuma (approximate map). LP Central America (6th ed, published 2007) says: "$35, one hour. […] boats leave several times daily. Reserve with a tour operator." Googling around, I think the price now is $40 - $45. (To me this looks more uncertain option, since you need to book the boat in advance, and I couldn't find definitive info on how many daily boats there are.)

Sources: Moon Handbooks Costa Rica (5h ed, 2004), LP: Central America on a Shoestring (6th ed, 2007) and Wikitravel.

Moving around with buses in Costa Rica is easy and cheap, in my experience, but having a good guidebook (such as most recent Lonely Planet or Moon guide) is advisable for figuring out which routes exists and where exactly the buses leave etc.

Secondly, I will be there for a week and would like to know what some of the cannot miss sights are to see while I am there.

Not sure if there are many sights per se in Montezuma, but here's a general description and some activities, again from the Moon CR guide (by Christopher P. Baker):

Montezuma is a charming beachside retreat popular with budget-minded backpackers and counterculture travelers seeking an offbeat experience. It's blessed with budget accommodations and a marvelous beach. The fantastic beaches east of Montezuma are backed by forest-festooned cliffs from which streams tumble down to the sands. Monkeys frolic in the forests behind the beach.

There's the Nicolas Weissenburg Absolute Reserve to protect the shoreline and forested hills, but it is "strictly off-limits". However, you can go horseback riding and hiking along trails edging the reserve.

There are companies (the guidebook mentions Aventuras Montezuma and Montezuma Expeditions) offering horseback rides, fishing, kayaking, snorkeling, and biking, as well as tours to Isla Tortuga and Cabo Blanco.

For example, taking a day trip to the "stunningly beautiful" Isla Tortuga sounds like a nice idea.